Chapter XV Final Remarks
Problems requiring investigation—
Giant nerve-cells and giant-fibres; their comparison in fishes and in arthropods; blood- and lymph-corpuscles; nature of the skin; origin of system of unstriped muscles; origin of the sympathetic nervous system; biological test of relationship.
Criticism of Balanoglossus theory.—Theory of parallel development.—Importance of the theory advocated in this book for all problems of Evolution.
The discussion in the last chapter on the “Principles of Embryology” completes the evidence which I am able to offer up to the present time in favour of my theory of the “Origin of Vertebrates.” There are various questions which I have left untouched, but still are well worth discussion, and may be mentioned here. The first of these is the significance of the giant nerve-cells and giant nerve-fibres so characteristic of the brain-region of the lower vertebrates. In most fishes two very large cells are most conspicuous objects in any transverse section of the medulla oblongata at the level of entrance of the auditory nerves. Each of these cells gives off a number of processes, some of which pass in the direction of the auditory nerves and one very large axis-cylinder process which forms a giant-fibre, known by the name of a Mauthnerian fibre. Each Mauthnerian fibre crosses the middle line soon after its origin from the giant-cell, and passes down the spinal cord on the opposite side right to the tail. Here, near the end of the spinal cord, it breaks up into smaller fibres, which are believed by Fritsch and others to pass out directly into the ventral roots to supply the muscles of the tail. Thus Bela Haller says: “The Mauthnerian fibres are known to give origin to certain fibres which supply the ventral roots of the last three spinal nerves, so that their terminal branches serve, in all probability, for the innervation of the muscles of the tail-fin.” They do not occur in the eel, according to Haller, or in Silurus, according to Kölliker. Their absence in those fishes, in which a well-developed tail-fin is also absent, increases the probability of the truth of Fritsch’s original conclusion that these giant-fibres are associated axis-cylinders for certain definite co-ordinated movements of the fish, especially for the lateral movement of the tail.
In Ammocœtes, instead of two Mauthnerian fibres, a number of giant-fibres are found. They are called Müllerian fibres, and arise from giant-cells which are divisible into two groups. The first group consists of three pairs situated headwards of the level of exit of the trigeminal nerves. Two of these lie in front of the level of exit of the oculomotor nerves, and one pair is situated at the same level as the origin of the oculomotor nerves. The second group consists of a number of cells on each side at the level of the entrance of the fibres of the auditory nerves.
The Müllerian fibres largely decussate, as described by Ahlborn, and then become the most anterior portion of the white matter of the spinal cord, forming a group of about eight fibres on each side (Fig. 73). A few fibres are also found laterally, and slightly dorsally, to the grey matter. These giant-fibres pass down the spinal cord right to the anal region; their ultimate destination is unknown. Mayer considers that in the first part of their course they correspond to those tracts of fibres known as the “posterior longitudinal bundles” in other vertebrates. I imagine, therefore, that the spinal part of their course represents the two antero-lateral descending tracts. The second group of giant-cells, which appears to have some connection with the auditory nerves, may represent “Deiter’s nucleus.” The whole system is probably the central nervous part of a co-ordination mechanism, which arises entirely in the pro-otic or prosomatic region of the brain—the great co-ordinating and equilibrating region par excellence.
If we turn now to the arthropod it is a striking coincidence that in the crayfish and in the lobster the work of Retzius, of Celesia, of Allen, and of many others demonstrates the existence of an equilibration-mechanism for the swimming movements of the tail-muscles, which is carried out by means of giant-fibres. These giant-fibres are the axis-cylinder processes of giant-cells, situated exclusively in the brain-region, and they run through the whole ventral ganglionic chain in order to supply the muscles of the tail. In the ventral nerve-cord of the crayfish, according to Retzius, two specially large giant-fibres exist, each of which breaks up, at the last abdominal ganglion, into smaller fibres, which pass directly out with the nerves to the tail-fin. Allen has shown that, in addition to these two specially large giant-fibres, there are a number of others, some of which, similarly to the Müllerian fibres of Ammocœtes, cross the middle line, while some do not. Each of these arises from a large nerve-cell and passes to one or other of the last pair of abdominal ganglia. The latter fibres, he says, send off collaterals, while the two specially large giant-fibres do not. The cells which give origin to all these large, long fibres are situated in or in front of the prosomatic region of the brain, similarly to the giant-cells, which give rise to the corresponding Müllerian fibres of Ammocœtes. I do not know how far this system is represented in Limulus or Scorpio.
It is, to my mind, improbable that the Mauthnerian fibres pass out directly as motor fibres to the muscles of the tail-fin; it is more likely that they are conducting paths between the equilibration-mechanism in connection with the VIIIth nerve and the spinal centres for the movements of the tail. Similarly, with respect to the arthropod, it is difficult to believe that the motor fibres for the tail-muscles arise in the brain-region. In either case, the striking coincidence remains that the movements of the tail-end of the body are regulated by means of giant-fibres which arise from giant-cells in the head-region of the body in both the Arthropoda and the lowest members of the Vertebrata.
The meaning of this system of giant-cells and giant-fibres in both classes of animals is well worthy of further investigation.
Another important piece of comparative work which ought to help in the elucidation of this problem is the comparison of the blood- and lymph-corpuscles of the vertebrate with those of the invertebrate groups. As yet, I have not myself made any observations in this direction, and feel that it is inadvisable to discuss the results of others until I know more about the facts from personal observation.
The large and important question of the manner of formation of the vertebrate skin has only been considered to a slight extent. A much more thorough investigation requires to be made into the nature of the skin of the oldest fishes in comparison with the skin of Ammocœtes on the one side, and of Limulus and the Palæostraca on the other.
The muscular system requires further investigation, not so much the different systems of the striated voluntary musculature—for these have been for the most part compared in the two groups of animals in previous chapters—as the involuntary unstriped musculature, about which no word has been said. The origin of the different systems of unstriped muscles in the vertebrate is bound up with the origin of the sympathetic system and its relation to the cranial and sacral visceral systems. The reason why I have not included in this book the consideration of the sympathetic nervous system is on account of the difficulty in finding any such system in Ammocœtes. Also, so far as I know, the distribution of unstriped muscle in Ammocœtes has not been worked out.
One clue has arisen quite recently which is of great importance, and must be worked out in the future, viz. the extraordinary connection which exists between the action of the sympathetic nervous system and the action of adrenalin. This substance, which is obtained from the medullary part of the adrenal or suprarenal glands, when injected into an animal produces the same effects as stimulation of the nerves, which belong to the lumbo-thoracic outflow of visceral nerves, i.e. the system known as the sympathetic nervous system, which is distinct from both the cranial and sacral outflows of visceral nerves. The similarity of its action to stimulation of nerves is entirely confined to the nerves of this sympathetic system, and never resembles that of either the cranial or sacral visceral nerves.
Another most striking fact which confirms the great importance of this connection between the adrenals and the sympathetic nervous system from the point of view of the evolution of the latter system is that the extract of the adrenals always produces the same effect as that of stimulation of the nerves of the sympathetic system, whatever may be the animal from which the extract is obtained. Thus adrenalin obtained from the elasmobranch fishes will produce in the highest mammal all the effects known to occur upon stimulation of the nerves of its sympathetic system.
Further, the cells, which are always associated with the presence of this peculiar substance—adrenalin—stain in a characteristic manner in the presence of chromic salts. In Ammocœtes patches of cells which stain in this manner have been described in connection with blood-vessels in certain parts, so that, although I know of no definite evidence of the existence of cell-groups in Ammocœtes corresponding to the ganglia of the sympathetic system in other vertebrates, it is possible that further investigation into the nature and connection of these “chromaffine” cells may afford a clue to the origin of the sympathetic nervous system. At present it is premature to discuss the question further.
Finally, another test as to the kinship of two animals of different species must be considered more fully than I have been able to do up to the present time. This test is of a totally different nature to any put forth in previous pages. It is known as the “biological test” of relationship, and is the outcome of pathological rather than of physiological or anatomical research. It is possible that this test may prove the most valuable of all. At present we do not know sufficiently its limitations and its sources of error, especially in the case of cold-blooded animals, to be able to look upon it as decisive in a problem of the kind considered in this book.
The nature of this test is as follows: It has been found that the serum of the blood of another animal, when injected in sufficient quantity into a rabbit, will cause such a change in the serum of that rabbit’s blood that when it is added to the serum of the other animal a copious precipitate is formed, although the serum of normal rabbit’s blood when mixed with that of another animal will cause no precipitate whatever. This extraordinary production of a precipitate in the one case and not in the other indicates the production of some new substance in the rabbit’s serum in consequence of the introduction of the foreign serum into the rabbit, which brings about a precipitate when the rabbit’s serum containing it is mixed with the serum originally injected. The barbarous name “antibody” has been used to express this supposed substance in accordance with the meaning of such a word as “antitoxin,” which has been a long time in use in connection with preventive remedies against pathogenic bacteria. Now, it is found that the rabbit’s serum containing a particular “antibody” will cause a precipitate only when added to the serum of the blood of the animal from which the “antibody” was produced or to the serum of the blood of a nearly related animal.
Further, if that animal is closely related a precipitate will be formed nearly as copious as with the original serum, if more distantly related a cloudiness will occur rather than a precipitate, and if the relationship is still more distant the mixture of the two sera will remain absolutely clear. Thus this test demonstrates the close relationship of man to the anthropoid apes and his more distant relationship to monkeys in general. By this method very evident blood-relationships have been demonstrated, especially between members of the Mammalia.
I therefore started upon an investigation into the possibility of proving relationship in this way between Limulus and Ammocœtes, with the kind assistance of Mr. Graham Smith. I must confess I was not sanguine of success, as I thought the distance between Limulus and Ammocœtes was too great. Dr. Lee, of New York, kindly provided me with most excellent serum of Limulus, and the first experiments showed that the anti-serum of Limulus gave a most powerful precipitate with its own serum. Graham Smith then tried this anti-serum of Limulus with the serum of Ammocœtes, and to his surprise, and mine, he obtained a distinct cloudiness, indicative of a relationship between the two animals. This, however, is not considered sufficient, the reverse experiment must also succeed. I therefore, with Graham Smith, obtained a considerable amount of blood from the adult lampreys at Brandon, and produced an anti-serum of Petromyzon, which gave some precipitate with its own serum, but not a very powerful one. This anti-serum tried with Limulus gave no result whatever, but at the same time it gave no result with serum from Ammocœtes, so that the experiment not only showed that Petromyzon was not related to Limulus, but also was not related to its own larval form, which is absurd.
Considerable difficulties were encountered in preparing the Petromyzon anti-serum owing to the extreme toxic character of the lamprey’s serum to the rabbit; in this respect it resembled that of the eel. It is possible that the failure of the lamprey’s anti-serum was due to the necessity of heating the serum sufficiently to do away with its toxicity before injecting it into the rabbit. At this point the experiments have been at present left. It will require a long and careful investigation before it is possible to speak decisively one way or the other. At present the experiment is positive to a certain extent, and also negative; but the latter proves too much, for it proves that the larva is not related to the adult.
Some day I hope this “biological test” will be of use for determining the relationships of the Tunicata, the Enteropneusta, Amphioxus, etc., as well as of Limulus and Ammocœtes.
The origin of Vertebrates from a Palæostracan stock, as put forward in this book, gives no indication of the systematic position of the Tunicata or Enteropneusta. Neither the Tunicata nor Amphioxus can by any possibility be on the direct line of ascent from the invertebrate to the vertebrate. They must both be looked upon as persistent failures, relics of the time when the great change to the vertebrate took place. The Enteropneusta are on a different footing; in their case any evidence of affinity with vertebrates is very much more doubtful.
The observer Spengel, who has made the most exhaustive study of these strange forms, rejects in toto any connection with vertebrates, and considers them rather as aberrant annelids. The so-called evidence of the tubular central nervous system is worth nothing. There is not the slightest sign of any tubular nervous system in the least resembling that of the vertebrate. It is simply that in one place of the collar-region the piece of skin containing the dorsal nerve of the animal, owing to the formation of the collar, is folded, and thus forms just at this region a short tube. My theory explains in a natural manner every portion of the elaborate and complicated tube of the vertebrate central nervous system. In the Balanoglossus theory the evolution of the vertebrate tube in all its details from this collar-fold is simple guesswork, without any reasonable standpoint. Similarly, the small closed diverticulum of the gut in Balanoglossus, which is dignified with the name of “notochord,” has no right to the name. As I have already said, it may help to understand why the notochord has such a peculiar structure, but it gives no help to understanding the peculiar position of the notochord. The only really striking resemblance is between the gill-slits of Amphioxus and of the Enteropneusta. In this comparison there is a very great difficulty, very similar to that of the original attempts to derive vertebrates from annelids—the gill-slits open ventrally in the one animal and dorsally in the other. In both animals an atrial cavity exists which is formed by pleural folds, and in these pleural folds the gonads are situated so that the similarity of the two branchial chambers seems at first sight very complete. In the Enteropneusta, however, there are certain forms—Ptychodera—in which these pleural folds have not met in the mid-line in this branchial region, and in these it is plainly visible that these folds, with their gonads, spring from the ventral mid-line and arch over the dorsal region of the body. Equally clearly Amphioxus shows that its pleural folds, with the gonads, spring from the dorsal side of the animal, and grow ventralwards until they fuse in the ventral mid-line (cf. Fig. 168).
As far, then, as this one single striking similarity between Amphioxus and the Enteropneusta is concerned it necessitates the reversal of dorsal and ventral surfaces to bring the two branchial chambers into harmony.
Fig. 168.—Diagram illustrating the Position of the Pleural Folds and Gonads in Ptychodera (A) and Amphioxus (B) respectively.
Al., alimentary canal; D.A., dorsal vessel; V.A., ventral vessel; g., gonads; NC., notochord; C.N.S., central nervous system.
In a mud-dwelling animal, like Balanoglossus, which possesses no appendages, no special sense-organs, it seems likely enough that ventral and dorsal may be terms of no particular meaning, and consequently what is called ventral in Balanoglossus may correspond to what is dorsal in Amphioxus; in this way the branchial regions of the two animals may be closely compared. Such comparison, however, immediately upsets the whole argument of the vertebrate nature of Balanoglossus based on the relative position of the central nervous system and gut, for now that part of its nervous system which is looked upon as the central nervous system in Balanoglossus is ventral to the gut, just as in a worm-like animal, and not dorsal to it as in a vertebrate.
There is absolutely no possibility whatever of making such a detailed comparison between Balanoglossus and any vertebrate, as I have done between a particular kind of arthropod and Ammocœtes. In the latter case not only the topographical anatomy of the organs in the two animals is the same, but the comparison is valid even to microscopical structure. In the former case the origin of almost all the vertebrate organs is absolutely hypothetical, no clue is given in Balanoglossus, not even to the segmented nature of the vertebrate. The same holds good with the evidence from Embryology and from Palæontology. I have pointed out how strongly the evidence in both cases confirms that of Comparative Anatomy. In neither case is the strength of the evidence for Balanoglossus in the slightest degree comparable. In Embryology an attempt has been made to compare the origin of the cœlom in Amphioxus and in Balanoglossus. In Palæontology there is nothing, only an assumption that in the Cambrian and Lower Silurian times a whole series of animals were evolved between Balanoglossus and the earliest armoured fishes, which have left no trace, although they were able to hold their own against the dominant Palæostracan race. The strangeness of this conception is that, when they do appear, they are fully armoured, as in Pteraspis and Cephalaspis, and it is extremely hard luck for the believers in the Balanoglossus theory that no intermediate less armoured forms have been found, especially in consideration of the fact that the theory of the origin from the Palæostracan does not require such intermediate forms, but finds that those already discovered exactly fulfil its requirements.
One difficulty in the way of accepting the theory which I have advocated is perhaps the existence of the Tunicata. I cannot see that they show any affinities to the Arthropoda, and yet they are looked upon as allied to the Vertebrata. I can only conclude that both they and Amphioxus arose late, after the vertebrate stock had become well established, so that in their degenerated condition they give indications of their vertebrate ancestry and not of their more remote arthropod ancestry.
In conclusion, the way in which vertebrates arose on the earth as suggested in this book carries with it many important far-reaching conclusions with respect to the whole problem of Evolution.
When the study of Embryology began, great hopes were entertained that by its means it would be possible to discover the pedigree of every group of animals, and for this end all the stages of development in all groups of animals were sought for and, as far as possible, studied. It was soon found, however, that the interpretation of what was seen was so difficult, as to give rise to all manner of views, depending upon the idiosyncrasy of the observer. At his will he decided whether any appearance was cœnogenetic or palingenetic, with the result that, in the minds of many, embryology has failed to afford the desired clue.
At the same time, the geological record was looked upon as too imperfect to afford any real help; it was said, and is said, that the Cambrian and pre-Cambrian periods were so immense, and the animals discovered in the lower Silurian so highly organized, as to compel us to ascribe the origination of all the present-day groups to this immense early period, the animals of which have left no trace of their existence as fossils.
In consequence of, or at all events following upon, the supposed failure of embryology and of geology to solve the problem of the sequence of evolution of animal life, a new theory has arisen, which goes very near to the denial of evolution altogether. This is the theory of parallel development. It discards the old picture of a genealogical tree with main branches arising at different heights, these again branching and branching into smaller and smaller twigs, and substitutes instead the picture of the ribs of a fan, every rib running independently of every other, each group represented by a rib reaching its highest development on the circumference of the fan and coming nearer and nearer to a common point at the handle of the fan. This point of convergence, where all the groups ultimately meet, is so far back as to reach to the lowest living organisms.
This, in my opinion, unscientific and inconceivable suggestion has arisen largely in consequence of a conception which has become firmly fixed in the minds of very many writers on this subject—the conception that in the evolution of every group, the higher members of the group are the most specialized in the peculiarities of that group, and it is impossible to obtain a new group with different peculiarities from such specialized members. If, then, a higher group is to arise from a lower, it must arise from the generalized members of that lower group, in other words, from the lowest members or those nearly akin to the next lower group.
Similarly, the highest members of this latter group are too specialized, and again we must go to the more generalized members of the group. In this way each separate specialized group is put on one side, and so the conception of parallel development comes into being.
The evidence given in this book dealing with the origin of vertebrates strikes at the foundations of this belief, for it presents an image of the sequence of evolution of animal forms in orderly upward progress, caused by the struggle for existence among the members of the race dominant at the time, which brought about the origin of the next higher group not from the lowest members of the dominant group, but from some one of the higher members of that group.
The great factor in evolution has been throughout the growth of the central nervous system; from that group of animals which possessed the highest nervous system evolved up to that time the next higher group must have arisen.
In this way we can trace without a break, always following out the same law, the evolution of man from the mammal, the mammal from the reptile, the reptile from the amphibian, the amphibian from the fish, the fish from the arthropod, the arthropod from the annelid, and we may be hopeful that the same law will enable us to arrange in orderly sequence all the groups in the animal kingdom.
This very same law of the paramount importance of the development of the central nervous system for all upward progress will, I firmly believe, lead to the establishment of a new and more fruitful embryology, the leading feature of which will be, as suggested in the last chapter, not the attempt to derive from the blastula three germ-layers common to all animals, but rather two sets of organs—those which are governed by the nervous system and those which are not—and thus by means of the development of the central nervous system obtain from embryology surer indications of relationship than are given at present.
The great law of recapitulation, which asserts that the past history of the race is indicated more or less in the development of each individual, a law which of late years has fallen somewhat into disrepute, owing especially to the difficulty of interpreting the embryological history of the vertebrate, is triumphantly vindicated by the theory put forward in this book. Each separate vertebrate organ, one after the other, as shown in the last chapter, indicates in its development the manner in which it arose from the corresponding organ of the arthropod. There is no failure in the evidence of embryology, the failure is in the interpretation thereof.
So, too, my theory vindicates the geological method. There is no failure here; on the contrary, the record of the rocks proclaims with startling clearness not only the sequence of evolution in the vertebrate kingdom itself, but the origin of the vertebrate from the most highly-developed invertebrate race.
The study of the comparative anatomy of organs down to the finest details has always been a most important aid in finding out relationship between animals or groups of animals. My theory endorses this view to the uttermost, and especially indicates the study of the central nervous system and its outgoing nerves as that comparative study which is most likely to afford valuable results.
As for the individual, so for the nation; as for the nation, so for the race; the law of evolution teaches that in all cases brain-power wins. Throughout, from the dawn of animal life up to the present day, the evidence given in this book suggests that the same law has always held. In all cases, upward progress is associated with a development of the central nervous system.
The law for the whole animal kingdom is the same as for the individual. “Success in this world depends upon brains.”
BIBLIOGRAPHY AND INDEX OF AUTHORS
| Author’s name. | Title of Paper. | Pages of reference. |
|---|---|---|
| AHLBORN | “Untersuchungen über das Gehirn der Petromyzonten” | 210, 489 |
| Zeitsch. f. wiss. Zool. Vol. 39. 1883 | ||
| “Ueber die Segmentation des Wirbelthierkörpers” | 260 | |
| Zeitsch. f. wiss. Zool. Vol. 40. 1884 | ||
| AICHEL | “Vergleichende Entwicklungsgeschichte und Stammesgeschichte der Nebennieren” | 424, 428 |
| Arch. f. Mikr. Anat. Vol. 56. 1900 | ||
| ALCOCK | 135, 287, 288, 289, 304, 307, 347, 445 | |
| “The Peripheral Distribution of the Cranial Nerves of Ammocœtes” | 164, 171, 177, 188, 202, 297, 300, 310, 311, 316 | |
| Journ. of Anat. and Physiol. Vol. 33. 1898 | ||
| “On Proteid Digestion in Ammocœtes” | 58, 213, 442, 452 | |
| Journ. of Anat. and Physiol. Vol. 33. 1898 | ||
| ALLEN | “Studies on the Nervous System of Crustacea” | 489 |
| Q. J. Micr. Sci. Vol. 36. 1894 | ||
| ANDERSON, H. K. | 448, 470 | |
| “The Nature of the Lesions which hinder the Development of Nerve-cells and their Processes | 466, 467, 469 | |
| Journ. of Physiol. Vol. 28. 1902 | ||
| “On the Myelination of Nerve-fibres” | 467, 477 | |
| Report of the Brit. Assn. 1898 | ||
| APATHY | “Das leitende Element des Nervensystems und seine topographischen Beziehung zu den Zellen” | 467 |
| Mitth. a. d. Zool. Stat. zu Neapel. Vol. 12. 1896 | ||
| ASSHETON | “On the Phenomenon of the Fusion of the Epiblastic Layers in the Rabbit and in the Frog” | 42 |
| Q. J. Micr. Sci. Vol. 37. 1894 | ||
| “An Experimental Examination into the Growth of the Blastoderm of the Chick” | 154 | |
| Proc. of Roy. Soc. Vol. 60. 1896 | ||
| “On the Growth in Length of the Frog Embryo” | 154 | |
| Q. J. Micr. Sci. Vol. 37. 1894 | ||
| “A Re-investigation into the Early Stages of the Development of the Rabbit” | 154 | |
| Q. J. Micr. Sci. Vol. 37. 1894 | ||
| “The Primitive Streak of the Rabbit: the Causes which may determine its Shape, and the part of the Embryo formed by its Activity” | 154 | |
| Q. J. Micr. Sci. Vol. 37. 1894 | ||
| BALFOUR | ‘Comparative Embryology.’ Vol. 2 | 73, 74, 94, 103, 104, 120, 181, 259, 424 |
| London. 1881. Macmillan & Co. | ||
| “On the Origin and History of the Urino-genital Organs of Vertebrates” | 390, 392 | |
| Journ. of Anat. and Physiol. Vol. 10. 1876 | ||
| “On the Nature of the Organ in Adult Teleosteans and Ganoids, which is usually regarded as the Head-kidney or Pronephros” | 420 | |
| Q. J. Micr. Sci. Vol. 22. 1882 | ||
| BARKER | ‘The Nervous System’ | 470 |
| London. 1901 | ||
| BATESON | “The Ancestry of the Chordata” | 11 |
| Q. J. Micr. Sci. Vol. 26. 1886 | ||
| ‘Materials for the Study of Variation’ | 387 | |
| London. 1894 | ||
| BEARD | “The System of Branchial Sense Organs and their Associated Ganglia in Ichthyopsida” | 262, 281, 283 |
| Q. J. Micr. Sci. Vol. 26. 1885 | ||
| “The Development of the Peripheral Nervous System in Vertebrates” | 262, 281, 283 | |
| Q. J. Micr. Sci. Vol. 29. 1888 | ||
| “The Old Mouth and the New” | 318 | |
| Anat. Anzeiger. 1888 | ||
| “The Source of Leucocytes and the True Function of the Thymus” | 425, 426 | |
| Anat. Anzeiger. Vol. 18. 1900 | ||
| “The Parietal Eye of the Cyclostome Fishes” | 84 | |
| Q. J. Micr. Sci. Vol. 29. 1882 | ||
| BECK AND LANKESTER | “On the Muscular and Endo-skeletal Tissues of Scorpio” | 171, 222, 224, 247, 268-277 |
| Trans. Zool. Soc. Vol. 11. 1885 | ||
| BEECHER | “Natural Classification of the Trilobites” | 283, 351, 436, 437 |
| Amer. Journ. of Sci. Ser. 4. Vol. 3. 1897 | ||
| BELL, C. | ‘The Nervous System of the Human Body’ | 155, 156, 183 |
| London. 1830 | ||
| BELLONCI | “Système Nerveux et Organes des sens du Sphæroma serratum” | 62, 90, 92, 101 |
| Archiv. Ital. de Biol. Vol. 1. 1882 | ||
| “Sur la structure et les rapports des lobes olfactives dans les Arthropods superieurs et les Vertébrés” | 221,225 | |
| Archiv. Ital. de Biol. Vol. 3. 1883 | ||
| BENHAM AND LANKESTER | “On the Muscular and Endo-skeletal Systems of Limulus” | 143, 171, 176, 177, 247 |
| Trans. Zool. Soc. Vol. 11. 1885 | ||
| BERGER | “Untersuchungen über den Bau des Gehirns und der Retina der Arthropoden” | 88-92, 97, 100, 101 |
| Arbeit. a. d. Zool. Instit. Wien. Vol. 1. 1878 | ||
| BERGH | “Neue Beiträge zur Embryologie der Anneliden” | 478 |
| Zeitsch. f. wiss. Zool. Vol. 50. 1890 | ||
| BERKLEY | “The Intrinsic Nerves of the Kidney” | 477 |
| Bulletin of the Johns Hopkins Hospital. Vol. 4 | ||
| BERNARD | ‘The Apodidæ: a Morphological Study’ | 284 |
| Nature Series. 1892 | ||
| BERTKAU | “Beiträge zur Kenntniss der Sinnesorgane der Spinnen. 1. Die Augen der Spinnen” | 369 |
| Archiv. f. mikr. Anat. Vol. 27. 1886 | ||
| BIEDERMANN | ‘Electro-physiology’ | 20 |
| Translated by F. A. Welby. London. 1896 | ||
| BLANCHARD | Quoted by Huxley | 225 |
| ‘L’Organisation du Règne Animal. Arachnides’ | 109, 177, 190, 206, 313, 315 | |
| Paris. 1852 | ||
| BLES | “The Correlated Distribution of Abdominal Pores and Nephrostomes in Fishes” | 431 |
| Journ. of Anat. and Physiol. Vol. 32. 1898 | ||
| BOBRETSKY | ‘Development of Astacus and Palæmon’ | 74 |
| Kiew. 1873 | ||
| BOURNE AND LANKESTER | See Lankester and Bourne. | |
| BOVERI | “Die Nieren Canälchen des Amphioxus” | 392, 395, 402, 407, 412, 426, 427 |
| Zool. Jahrbuch. Vol. 5. 1892 | ||
| BRAEM | “Was ist ein Keimblatt” | 460, 461, 462 |
| Biol. Centralblatt. Vol. 15. 1895 | ||
| BRAUER | “Beiträge zur Kenntniss der Entwicklungsgeschichte des Skorpions” | 62, 167, 222, 237, 281, 482 |
| Zeit. f. wiss. Zool. Part I. Vol. 57. 1894 Part II. Vol. 59. 1895 | ||
| “Beiträge zur Kenntniss der Entwicklung und Anatomie der Gymnophionen.” III. | 393, 394, 400, 402 | |
| “Die Entwicklung der Excretionsorgane” Zool. Jahrbuch. Vol. 16. 1902 | ||
| “Ueber die Entwicklung von Hydra” | 473 | |
| Zeit. f. wiss. Zool. Vol. 52. 1891 | ||
| BÜTSCHLI | “Notiz zur Morphologie des Auges der Muscheln” | 114 |
| Festschrift des Natur-hist-med. Vereins zu Heidelberg. 1886 | ||
| BUJOR | “Contribution a l’étude de la métamorphose de l’Ammocœtes branchialis en Petromyzon Planeri” | 135, 304 |
| Revue Biologique du Nord de la France. Vol. 3. 1891 | ||
| CARLSON | 177, 315, 316 | |
| CELESIA | ‘Differenziamento della proprietà inibitoria e dei funzioni coordinatrici nella catena gangliare dei crustacei decapodi’ | 489 |
| Genoa. 1897 | ||
| CLAUS | “Untersuchungen über den Organismus und Entwicklung von Branchipus und Artemia” | 90-92, 97, 100, 396 |
| Arbeit a.d. Zool. Institut. Wien. Vol. 6. 1886 | ||
| COPE | “On the Phylogeny of the Vertebrata” | 343 |
| Proc. Amer. Philos. Soc. Vol. 30. 1892 | ||
| CRONEBERG | “Ueber die Mundtheile der Arachniden” | 221-224, 241 |
| Archiv. f. Naturgeschichte. 1880 | ||
| CUÉNOT | “Études sur le sang et les glandes lymphatiques dans la série animale; 2nd partie; invertébrés” | 422 |
| Arch. d. Zool. exper. gen. 2nd Ser. Vol. 9. 1891 | ||
| CUNNINGHAM, J. T. | “The Significance of Kupffer’s Vesicle, with Remarks on other Questions of Vertebrate Morphology” | 318 |
| Q. J. Micr. Sci. Vol. 25. 1885 | ||
| “The Nephridia of Lanice conchilega” | 403 | |
| Nature. Vol. 36. 1887 | ||
| DANA | “On Cephalization” | 53 |
| Mag. of Nat. Hist. 1863 | ||
| DEAN-BASHFORD | ‘Fishes, Living and Fossil’ | 344 |
| New York. 1895 | ||
| “On the Embryology of Bdellostoma Stouti” | 405 | |
| Festschr. z. siebenzigsten Geburtstag. von C. v. Kupffer. Jena. 1899 | ||
| DENDY | “On the Parietal Sense-organs and Associated Structures in the New Zealand Lamprey (Geotria australis)” | 80, 82 |
| Q. J. Micr. Sci. Vol. 51. 1907 | ||
| DIETL | “Die Organisation des Arthropoden Gehirns” | 101 |
| Zeitsch. f. wiss. Zool. Vol. 27. 1876 | ||
| DOHRN | ‘Der Ursprung der Wirbelthiere und das Princip des Functionswechsels’ | 14, 60, 185, 186, 317, 318 |
| Leipzig. 1875 | ||
| Studien zur Urgeschichte des Wirbelthiere Körpers. VIII. “Die Thyroidea bei Petromyzon, Amphioxus, und Tunicaten” | 188, 195-198, 199, 212, 213 | |
| Mitth. Zool. Stat. z. Neapel. Vol. 6. 1886 | ||
| “Neue Grundlagen zur Beurtheilung der Metamerie des Kopfes” | 262, 263, 279 | |
| Mitth. Zool. Stat. z. Neapel. Vol. 9. 1890 | ||
| Studien zur Urgeschichte des Wirbelthiere Körpers. XIII. “Ueber Nerven und Gefässe bei Ammocœtes und Petromyzon Planeri” | 167, 314, 337 | |
| Mitth. Zool. Stat. z. Neapel. Vol. 8. 1888 | ||
| DREVERMANN | “Ueber Pteraspis dunensis” | 29, 30 |
| Zeitschr. d. Deutsch. Geol. Gesellschaft. Vol. 56. 1904 | ||
| EDGEWORTH | “The Development of the Head-muscles in Gallus domesticus, and the Morphology of the Head-muscles in the Sauropsida” | 266 |
| Q. J. Micr. Sci. Vol. 51. 1907 | ||
| EDINGER | ‘Anatomy of Central Nervous System in Man and in Vertebrates’ | 17, 264 |
| Translated by Hall. 1899 | ||
| v. EICHWALD | “Die Thier- und Pflanzenreste des alten rothen Sandsteins und Bergkalks im Nowgorodschen Gouvernement” | 327 |
| Bull. Sci. de l’Acad. Impér. d. St. Petersbourg. 1840 | ||
| EISIG | “Die Seiten-organe und becherförmigen Organe der Capitelliden” | 357 |
| Mitth. a. d. Zool. Stat. z. Neapel. Vol. 1. 1879 | ||
| “Capitelliden” | 357 | |
| Faun. u. Flor. d. Golfes v. Neapel. Vol. 16. 1887 | ||
| ELLIOTT | “On the Innervation of the Ileo-colic Sphincter” | 449 |
| Journ. of Physiol. Vol. 31. 1904 | ||
| EMERY | Quoted by Weldon | 420 |
| FOSTER, M. | Text-book of Physiology | 108 |
| FREUND | “Die Beziehungen der Schilddrüse zu den weiblichen Geschlechtsorganen” | 215 |
| Deutsch. Zeitsch. f. Chirugie. Vol. 18. 1883 | ||
| FRITSCH, G. | ‘Untersuchungen über den feineren Bau des Fischgehirns’ | 488, 489 |
| Berlin. 1878 | ||
| FRORIEP | “Ueber Anlagen von Sinnesorganen am Facialis, Glossopharyngeus und Vagus, über die genetische Stellung des Vagus zum Hypoglossus, und über die Herkunft der Zungenmusculatur” | 261, 262, 281, 283 |
| Arch. f. Anat. u. Physiol; Anat. Abtheil. 1885 | ||
| FÜRBRINGER, M. | ‘Ueber die Spino-occipetalen Nerven der Selachier und Holocephalen’ | 276-278, 409 |
| Fest-schrift für Carl Gegenbaur. 1897 | ||
| GAUBERT | ‘Recherches sur les organes des sens et sur les systèmes tegumentaire, glandulaire et musculaire des appendices des arachnides’ | 364, 368-375 |
| Paris. 1892 | ||
| GEGENBAUR | “Anatomische Untersuchung eines Limulus” | 20, 358-360 |
| Abhandl. d. Naturforsch. Gesellsch. z. Halle. Vol. 4. 1858 | ||
| “Ueber die Skeletgewebe der Cyclostomen” | 181 | |
| Jen. Zeitschrift. Vol. 5. 1870 | ||
| Untersuchungen zur vergleichende Anatomie der Wirbelthiere III. Heft. ‘Das Kopfskeletder Selachiern’ | 151, 259, 261 | |
| Leipzig. 1872 | ||
| ‘Grundriss der vergleichenden Anatomie’ | 392 | |
| Leipzig. 1878 | ||
| v. GEHUCHTEN | “De l’origine du pathétique et de la racine supérieure du trijumeau” | 264 |
| Acad. d. Sci. Belg. Bulletin. 3rd Ser. Vol. 29. 1895 | ||
| GOETHE | 258 | |
| GÖTTE | ‘Entwicklungsgeschichte der Unke’ | 101, 102, 114 |
| Leipzig. 1875 | ||
| GOLGI | 72, 465, 477 | |
| GOODRICH | “On the Structure of the Excretory Organs of Amphioxus” | 395, 396, 477 |
| Q. J. Micr. Sci. Vol. 45. 1902 | ||
| “On the Nephridia of the Polychæta.” Parts I., II., III. | 395 | |
| Q. J. Micr. Sci. Vols. 40, 41, 43 | ||
| “On the Excretory Organs of Amphioxus” | 477 | |
| Proc. Roy. Soc. Vol. 69. 1902 | ||
| GRABER | “Die Chordo-tonalen Sinnesorgane und das Gehör der Insecten” | 364, 369-371 |
| Archiv. f. Mikr. Anat. Vols. 20 and 21. 1882 | ||
| GRENACHER | ‘Untersuchungen über das Sehorgan der Arthropoden’ | 76, 100 |
| Göttingen. 1879 | ||
| GUDDEN | Quoted in Obersteiner | 264 |
| HAECKEL | 461, 462 | |
| HALLER, BELA | “Untersuchungen über die Hypophyse und die Infundibulärorgane” | 320, 321 |
| Morph. Jahrbuch. Vol. 25. 1898 | ||
| “Untersuchungen über das Rückenmark der Teleostier” | 488 | |
| Morph. Jahrbuch. Vol. 23. 1895 | ||
| HARDY | “On the Histological Features and Physiological Properties of the Post-œsophageal Nerve-cord of the Crustacea” | 110, 159 |
| Phil. Trans. Roy. Soc. 1894. B. | ||
| HARDY AND MACDOUGALL | “On the Structure and Functions of the Alimentary Canal of Daphnia” | 112, 206 |
| Proc. Camb. Phil. Soc. Vol. 8. 1893 | ||
| HATSCHEK | “Die Metamerie des Amphioxus und des Ammocœtes” | 289, 300, 337 |
| Anat. Anzeig., 7 Jahrgang, 1892. Verhandl. d. Anat. Gesell. in Wien, p. 136 | ||
| “Studien über Entwicklung des Amphioxus” | 407 | |
| Arbeit. d. Zool. Inst. z. Wien. Vol. 4. 1881 | ||
| Quoted by Lankester | 475 | |
| HAZEN | See Patten and Hazen. | |
| HEIDENHAIN | 258, 259 | |
| HEIDER | See Korschelt and Heider. | |
| HENSEN | “Zur Entwicklung des Nervensystem” | 465, 466 |
| Virchows Archiv. Vol. 30. 1864 | ||
| HENSEN AND VÖLCKERS | 265, 266 | |
| Archiv. f. Opthalmol. Vol. 24. 1878 | ||
| HERTWIG, O., AND SAMASSA | Quoted in Zeigler’s ‘Lehrbuch der vergleichenden Entwicklungsgeschichte der niederen Wirbelthiere.’ 1902 | 485 |
| HIS | “Die Neuroblasten und deren Entstehung im embryonalen Mark” | 465, 466 |
| Archiv. f. Anat. u. Physiol. Anat. Abth. 1889 | ||
| HOFFMANN | “Ueber die Metamerie des Nachhirns und Hinterhirns, und ihre Beziehung zu den segmentalen Kopfnerven bei Reptilien embryonen” | 276 |
| Zool. Anzeiger. Vol. 12. 1889 | ||
| HOLM | “Ueber die Organisation des Eurypterus Fischeri” | 192, 240, 241, 306 |
| Mem. d. l’Acad. Imp. d. Sci. d. St. Petersbourg. Vol. 8. 1898 | ||
| HOYER | “Ueber den Nachweis des Mucins in Geweben Mittelst der Färbe-Methode” | 131 |
| Archiv. f. Mikr. Anat. Vol. 36. 1890 | ||
| HUXLEY | “Hunterian Lectures.” 1869 | 124, 258, 259 |
| “On the Structure of the Mouth and Pharynx of the Scorpion” | 222, 225, 271 | |
| Q. J. Micr. Sci. Vol. 8. 1860 | ||
| “On the Anatomy and Affinities of the Genus Pterygotus” | 238 | |
| Mem. of the Geol. Survey. Monograph I. 1859 | ||
| “On Cephalaspis and Pteraspis” | 327 | |
| Q. J. of Geol. Soc. Vol. 14. 1858 | ||
| JAEKEL | “Ueber Tremataspis und Patten’s Ableitung der Wirbelthiere von Arthropoden” | 329, 339, 340, 351 |
| Protocoll der Deutschen Geolog. Gesellschaft, p. 84; in Zeitsch. d. Deutschen Geologischen Gesellsch. Vol. 55. 1903 | ||
| “Ueber die Organisation und systematische Stellung der Asterolepiden” | 345 | |
| Ibid., p. 41 | ||
| JOHNSON | “Contributions to the Comparative Anatomy of the Mammalian Eye, chiefly based on Opthalmoscopic Examination” | 70 |
| Phil. Trans. Roy. Soc. B. Vol. 194. 1901 | ||
| JOSEPH | “Ueber das Achsenskelett des Amphioxus” | 444 |
| Zeitsch. f. wiss. Zool. Vol. 59. 1895 | ||
| JULIN AND VAN BENEDEN | Recherches sur l’Organisation des Ascidies simples. “Sur l’hypophyse,” etc. | 425 |
| Archives de Biologie. Vol. 2. 1881 | ||
| KAENSCHE | “Beiträge zur Kenntniss der Metamorphose des Ammocœtes branchialis in Petromyzon” | 135, 304 |
| Schneider’s Beiträge. Vol. 2. 1890 | ||
| v. KENNEL | “Entwickelungsgeschichte von Peripatus Edwardsii und Peripatus torquatus.” II. Theil | 398, 399, 411 |
| Arbeit. a. d. Zool. Zoot. Instit. Würzburg. Vol. 8. 1888 | ||
| KERR | “On some Points in the Early Development of Motor Nerve-trunks and Myotomes in Lepidosiren paradoxa” | 461, 466, 478 |
| Trans. Roy. Soc. Edin. Vol. 41. 1904 | ||
| KILLIAN | “Zur Metamerie des Selachierkopfes” | 262 |
| Verhandl. d. Anat. Gesell. Versamml. in München. 1891 | ||
| KISHINOUYE | “On the Development of Limulus longispina” | 167, 238, 252, 253, 273, 320, 382 |
| Journ. of Coll. of Sci., Tokio. Vol. 5. 1891 | ||
| KLEINENBERG | Quoted by Beard | 318 |
| v. KÖLLIKER | “Die obere Trigeminus-Wurzel” | 280 |
| Arch. f. Mikr. Anat. Vol. 53. 1899 | ||
| v. KÖLLIKER AND TERTERJANZ | Handbuch der Gewebe-Lehre. 6th Auflage. 1893 | 264, 425, 488 |
| KOHL | “Rudimentäre Wirbelthieraugen” | 94, 96, 99, 101 |
| Bibliotheca Zoologica. Leukart und Chun. Vol. 4 and Vol. 5 | ||
| KOHN | “Ueber den Bau und die Entwicklung der sogenannten Carotis-drüse” | 428 |
| Archiv. f. Mikr. Anat. Vol. 56. 1900 | ||
| KORSCHELT AND HEIDER | ‘Text-book of the Embryology of the Invertebrates.’ Translated by M. Bernard. 1900. Part III. and Part IV. | 27, 73, 88, 114-116, 397, 429, 431 |
| KOWALEWSKY | “Ein Beitrag zur Kenntniss der Excretionsorgane der Pantopoden” | 421 |
| Mem. d. l’Acad. d. Imp. d. Sci. d. St. Petersbourg. Ser. VII. Vol. 38. 1890 | ||
| “Une nouvelle glande lymphatique chez le scorpion d’Europe” | 423 | |
| Ibid. Ser. VIII. Vol. 5. 1897 | ||
| “Étude Biologique sur les Clepsines” | 421 | |
| Ibid. Ser. VIII. Vol. 5. 1897 | ||
| “Ein Beitrag zur Kenntniss der Excretionsorgane” | 420, 422, 472 | |
| Biologisches Centralblatt. 1889 | ||
| “Weitere Studien über die Entwicklungsgeschichte des Amphioxus lanceolatus” | 409, 410 | |
| Archiv. f. Mikr. Anat. Vol. 13. 1877 | ||
| KRIEGER | “Ueber das Centralnervensystem des Flusskrebses | 101 |
| Zeitsch. f. wiss. Zool. Vol. 33. 1880 | ||
| v. KUPFFER | ‘Studien zur vergleichenden Entwicklungsgeschichte des Kopfes der Kranioten.’ ______ Heft. 1. ‘Die Entwicklung des Kopfes von Acipenser’ | 318, 319, 320, 440 |
| München. 1893 | ||
| Heft. 2. ‘Die Entwicklung des Kopfes von Ammocœtes Planeri’ | 300, 440 | |
| München. 1894 | ||
| ______ Heft. 3. ‘Die Entwicklung der Kopfnerven von Ammocœtes Planeri.’ ______ Dritter Abschnitt. ‘Die Metamorphose des larvalen Nervensystems des Kopfes’ | 228, 263, 282, 283, 405, 458 | |
| München. 1895 | ||
| LANG | ‘Text-book of Comparative Anatomy.’ Translated by H. M. and M. Bernard | 357 |
| LANGERHANS | “Untersuchungen über Petromyzon Planeri” | 94-101, 301, 405 |
| Bericht v. d. Verhandl. d. Naturforsch. Gesellsch. z. Freiburg. 1873 | ||
| LANGLEY | Schäfer’s ‘Text-book of Physiology.’ Vol. 2. 1900 | 2, 3, 448 |
| LANKESTER | Article “Vertebrata” in the ‘Encyclopædia Britannica’ | 484 |
| “On the Skeleto-trophic Tissues and Coxal Glands of Limulus, Scorpio, and Mygale | 137, 139, 253, 320, 321 | |
| Q. J. Micr. Sci. Vol. 24. 1884 | ||
| “Limulus an Arachnid” | 62, 238, 241, 306, 361, 366 | |
| Q. J. Micr. Sci. Vol. 21. 1881 | ||
| ‘Extinct Animals’ | 22, 150, 345 | |
| London. Constable & Co. 1906 | ||
| A treatise on Zoology. Edited by E. Ray Lankester. Part II. ‘The Entero-cœla and the Cœlomocœla’ | 472-478 | |
| LANKESTER AND POWRIE | “A Monograph of the Fishes of the Old Red Sandstone of Britain.” Part I. “The Cephalaspidæ” | 29, 275, 327, 339, 345 |
| Palæontographical Soc. 1868 | ||
| LANKESTER, BENHAM, AND BECK | “On the Muscular and Endo-skeletal Systems of Limulus and Scorpio, with some Notes on the Anatomy and Generic Characters of Scorpions” | 177, 222, 224, 313 |
| Trans. Zool. Soc. Vol. 11. 1885 | ||
| LANKESTER AND BOURNE | “The Minute Structure of the Lateral and Central Eyes of Scorpio and Limulus” | 74, 81-83 |
| Q. J. Micr. Sci. Vol. 23 | ||
| LANKESTER AND WILLEY | “The Development of the Atrial Chamber of Amphioxus” | 409 |
| Q. J. Micr. Sci. Vol. 31. 1890 | ||
| LANKESTER AND GULLAND | “Evidence in Favour of the View that the Coxal Gland of Limulus and of other Arachnids is a Modified Nephridium” | 429 |
| Q. J. Micr. Sci. Vol. 25. 1885 | ||
| LATREILLE | 221 | |
| LAURIE | “The Anatomy and Relations of the Eurypteridæ” | 237 |
| Trans. Roy. Soc. Edin. Vol. 37. 1893 | ||
| “On a Silurian Scorpion and some Additional Eurypterid Remains from the Pentland Hills | 238, 239 | |
| Ibid. Vol. 34. 1899 | ||
| LEYDIG | 91 | |
| LOCY | “Contributions to the Structure and Development of the Vertebrate Head” | 179, 262 |
| Journ. Morph. Vol. 11. 1895 | ||
| LOEB, LEO, AND R. M. STRONG | “On Regeneration in the Pigmented Skin of the Frog, and on the Character of the Chromatophores” | 470 |
| Amer. Jour. of Anat. Vol. 3. 1904 | ||
| LOWNE | ‘The Anatomy, Physiology, Morphology, and Development of the Blow-fly’ | 369, 370, 375 |
| London. 1895 | ||
| LUGARO | Quoted by Anderson | 467 |
| LWOFF | “Ueber den Zusammenhang von Markrohr und Chorda beim Amphioxus und ähnliche Verbältnisse bei Anneliden” | 444 |
| Zeitsch. f. wiss. Zool. Vol. 56. 1893 | ||
| MAAS | “Ueber Entwicklungstadien der Vorniere und Urniere bei Myxine” | 392, 402, 412, 419 |
| Zool. Jahrbuch. Vol. 10. 1897 | ||
| MACBRIDE | “Further Remarks on the Development of Amphioxus” | 410 |
| Q. J. Micr. Sci. Vol. 43. 1900 | ||
| McDOUGALL | See Hardy and McDougall. | |
| MACLEOD | “Recherches sur la structure et la signification de l’appareil respiratoire des Arachnides” | 169, 174 |
| Archiv. de Biol. Vol. 5. 1881 | ||
| MAGNUS | “Versuche am überlebenden Dünndarm von Säugethieren” | 447 |
| Archiv. f. d. Ges. Physiologie. Vols. 102, 103. 1904 | ||
| MARK | 115 | |
| MARSHALL | “On the Head-cavities and Associated Nerves of Elasmobranchs” | 185, 186 |
| Q. J. Micr. Sci. Vol. 21. 1881 | ||
| “The Segmental Value of the Cranial Nerves” | 260 | |
| Journ. of Anat. and Physiol. Vol. 16. 1882 | ||
| MASTERMAN | “On the Diplochorda” | 16 |
| Q. J. Micr. Sci. Vol. 43. 1900 | ||
| MAURER | “Die Schilddrüse, Thymus und andere Schlundspaltenderivate bei den Eidechse” | 427, 428 |
| Morph. Jahrbuch. Vol. 27. 1899 | ||
| MAYER, F. | “Das Centralnervensystem von Ammocœtes” | 489 |
| Anat. Anzeig. Vol. 13. 1897 | ||
| MAYER, P. | “Ueber die Entwicklung des Herzens und der grossen Gefässstämme bei den Selachiern” | 179 |
| Mitth. a. d. Zool. Stat. z. Neapel. Vol. 7. 1887 | ||
| METSCHNIKOW | Quoted by Kowalewsky | 422 |
| MEYER | “Studien über den Körperbau der Anneliden” | 403 |
| Mitth. a. d. Zool. Stat. z. Neapel. Vol. 7. 1887 | ||
| MILNE-EDWARDS | “Anatomie des Limules” | 157, 159, 176, 177, 313 |
| Annales des Sciences Naturelles. Ser. 5. Vol. 17. 1872 | ||
| MINCHIN | A treatise on Zoology. Edited by Ray Lankester. Part II. “The Porifera and Cœlenterata” | 473 |
| MITSUKURI | “On the Fate of the Blastopore, the Relations of the Primitive Streak, and the Formation of the Posterior End of the Embryo in Chelonia,” etc. | 179 |
| Journ. Coll. Sci. Tokyo. Vol. 10. 1896 | ||
| MOTT | “Croonian Lectures of the Roy. Coll. of Physicians,” 1900 | 469 |
| MOTT AND HALLIBURTON | “On the Chemistry of Nerve-degeneration” | 469 |
| Phil. Trans. Roy. Soc. B. Vol. 194. 1901 | ||
| MÜLLER, J. | 1 | |
| “Vergleichende Anatomie der Myxinoiden” | 126 | |
| Abhandl. d. Kgl. Akad. d. Wiss. Berlin. 1834 | ||
| MÜLLER, W. | “Ueber die Stammes Entwickelung des Sehorgans der Wirbelthiere” | 96-100, 105, 108 |
| Festgabe C. Ludwig. Leipzig. 1874 | ||
| NEAL | “The Segmentation of the Nervous System in Squalus acanthias” | 179, 266, 300 |
| Bull. of Mus. Comp. Zool. Harvard. Vol. 31. 1898 | ||
| NESTLER | “Beiträge zur Anatomie und Entwicklungsgeschichte von Petromyzon Planeri” | 168, 171, 175, 445 |
| Archiv. f. Naturgesch. Jahrgang, 56. Vol. I. 1890 | ||
| NIESKOWSKI | “Der Eurypterus Remipes aus den obersilurischen Schichten der Insel Oesel” | 26, 239, 240 |
| Arch. f. d. Naturkunde Liv-Ehst-und Kurlands. 1st Ser. Vol. 3. 1858 | ||
| NUSBAUM, J. | “Einige neue Thatsachen zur Entwicklungsgeschichte des Hypophysis Cerebri bei Säugethieren” | 320 |
| Anat. Anzeiger. Vol. 12. 1896 | ||
| OBERSTEINER | ‘Central Nervous System.’ Translated by Hill. 1896 | 264, 280 |
| OKEN | 258 | |
| OWEN | “Essays on the Conario-Hypophysial Tract, and the Aspects of the Body in Vertebrate and Invertebrate Animals” | 14 |
| “On the Anatomy of the American King-crab (Limulus polyphemus)” | 211 | |
| Trans. Linn. Soc. Vol. 28. 1873 | ||
| PANDER | ‘Monographie der fossilen Fische des Silurischen Systems des russisch-baltischen Gouvernements’ | 327 |
| St. Petersbourg. 1856 | ||
| PARKER, G. H. | “The Retina and Optic Ganglia in Decapods, especially in Astacus” | 91, 93, 97 |
| Mitth. a. d. Zool. Stat. z. Neapel. Vol. 12. 1895 | ||
| “The Compound Eyes in Crustaceans” | 99, 100, 114 | |
| Bull. of Harvard Mus. of Comp. Zool. Vol. 20. 1890 | ||
| “The Function of the Lateral-line Organs in Fishes” | 357 | |
| Bull. of the Fisheries Bureau. Washington. Vol. 24. 1904 | ||
| “Studies on the Eyes of Arthropods” | 73, 79, 83-85, 114 | |
| Journ. of Morphology. Vols. 1 and 2. 1887 and 1889 | ||
| PARKER, W. K. | “On the Skeleton of the Marsipobranch Fishes” | 120, 125, 126, 131 |
| Phil. Trans. Roy. Soc. 1883 | ||
| PATTEN | “On the Origin of Vertebrates from Arachnids” | 352, 353 |
| Q. J. Micr. Sci. Vol. 31. 1890 | ||
| “On the Morphology and Physiology of the Brain and Sense-organs of Limulus” | 358-367, 371 | |
| Q. J. Micr. Sci. Vol. 35. 1893 | ||
| “New Facts concerning Bothriolepis” | 32, 351, 450 | |
| Biological Bulletin. Vol. 7. 1904 | ||
| “On the Structure and Classification of the Tremataspidæ” | 329 | |
| Mem. d. l’Acad. Imp. d. Sci. de St. Petersbourg. Vol. 13. 1903 | ||
| “On the Structure of the Pteraspidæ and Cephalaspidæ” | 415 | |
| The American Naturalist. Vol. 37. 1903 | ||
| “On the Appendages of Tremataspis” | 351 | |
| The American Naturalist. Vol. 37. 1903 | ||
| “On Structures Resembling Dermal Bones in Limulus” | 346 | |
| Anat. Anzeig. Vol. 9. 1894 | ||
| PATTEN AND HAZEN | “The Development of the Coxal Gland, etc., of Limulus Polyphemus” | 408 |
| Journ. of Morphol. Vol. 16. 1900 | ||
| PATTEN AND REDENBAUGH | Studies on Limulus. II. “The Nervous System of Limulus Polyphemus” | 314, 315, 381, 382 |
| Journ. of Morphol. Vol. 16. 1900 | ||
| PERLIA | Quoted by Edinger | 264 |
| PICK | Quo”ed by Ed”nger | 265 |
| PLATT | “A Contribution to the Morphology of the Vertebrate Head, based on a Study of Acanthias vulgaris” | 253, 265-267, 273, 274, 279, 284 |
| Journ. Morphol. Vol. 5. 1891 | ||
| “Fibres connecting the Central Nervous System and Chorda in Amphioxus” | 443 | |
| Anat. Anzeig. 1892 | ||
| PRICE | “Development of the Excretory Organs of Bdellostoma Stouti” | 394 |
| Zool. Jahrbuch. Vol. 10. 1897 | ||
| RABL | “Ueber die Metamerie des Wirbelthierkopfes” | 258, 262 |
| Verhandl. der Anat. Gesellsch. Versamml. in Wien. Anat. Anzeig. 1892 | ||
| “Die Entwicklung und Structur der Nebennieren bei den Vögeln” | 424 | |
| Arch. f. mikr. Anat. Vol. 38. 1891 | ||
| RAMÓN Y. CAJAL | 72, 465 | |
| RATHKE | “Anatomie des Querders” | 161, 169, 304 |
| Naturforsch. Gesellsch. zu Dantzig. Vol. 2. 1827 | ||
| REDENBAUGH | See Patten and Redenbaugh. | |
| REICHENBACH | “Entwicklungs-geschichte des Flusskrebses” | 98-100, 114 |
| Abhandl. d. Senckenbergischen Naturforsch. Gesellsch. Vol. 14. 1886. | ||
| RETZIUS | ‘Biologische Untersuchungen.’ Vol. 1. 1890. “Zur Kenntniss des Nervensystem der Crustaceen” | 20, 489 |
| ROHON | Die Obersilurischen Fische von Oesel. 1st Theil. “Thyestidæ und Tremataspidæ” | 32, 275, 276 |
| Mem. d. l’Acad. Imp. d. Sci. d. St. Petersbourg. 7th Ser. Vol. 38. 1892 | ||
| “Weitere Mittheilungen über die Gattung Thyestes” | 327-330, 339-341, 382 | |
| Bull. d. l’Acad. d. St. Petersbourg. 5th Ser. Vol. 4. 1896 | ||
| ROLPH | “Untersuchungen über den Bau des Amphioxus lanceolatus” | 444 |
| Morphol. Jahrbuch. Vol. 2. 1887 | ||
| RÜCKERT, J. | “Entwicklung der Excretionsorgane” | 392, 393, 400 |
| Merkel und Bonnet; Anat. Hefte. Vol. 1. 1891. | ||
| “Ueber die Entstehung der Excretionsorgane bei Selachiern” | 403 | |
| Archiv. f. Anatomie. 1888 | ||
| ST. HILAIRE | “Sur la Vertèbre” | 11 |
| La Revue Encyclopédique. 1822 | ||
| SAMASSA | “Bemerkungen über die Methode der Vergleichenden Entwicklungsgeschichte” | 462 |
| Biol. Centralblatt. Vol. 18. 1898 | ||
| SCHAFFER | “Ueber das Knorpelige Skelett von Ammocœtes” | 126-135 |
| Zeitsch. f. wiss. Zool. Vol. 61. 1896 | ||
| “Ueber die Thymusanlage bei Petromyzon Planeri” | 426-428 | |
| Sitzungsber. d. K. Akad d. Wiss. in Wien. Vol. 103. 1894 | ||
| SCHIMKÉWITSCH | “Sur la structure et sur la signification de l’Endosternite des Arachnides” | 143-145, 342 |
| Zool. Anzeig. 1893 | ||
| “Anatomie de l’Epeire” | 369 | |
| Ann. d. Sci. Nat. Vol. 17. 1884 | ||
| SCHMIDT | “Die Crustaceen-fauna der Eurypterenschichten von Rootziküll auf Oesel” | 190, 191, 236, 240, 329, 341 |
| Mem. d’Acad. Imp. d. Sci. d. St. Petersbourg. Vol. 31. 1883 | ||
| SCHMIEDEBERG | “Ueber die chemische Zusammensetzung des Knorpels” | 147 |
| Arch. f. exper. Pathol. und Pharmak. Vol. 28. 1891 | ||
| SCHNEIDER, A. | ‘Beiträge zur Anatomie und Entwicklungsgeschichte der Wirbelthiere’ | 128, 130, 172, 195, 197, 213, 310, 445 |
| Berlin. 1879 | ||
| SCHNEIDER, G. | “Ueber phagocytäre Organe und Chloragogenzellen der Oligochæta” | 421 |
| Zeitsch. f. wiss. Zool. Vol. 61. 1896 | ||
| SCOTT | “Notes on the Development of Petromyzon” | 42, 78, 111, 112, 406 |
| Journ. of Morphol. Vol. 1. 1887 | ||
| SEDGWICK | “A Monograph of the Development of Peripatus capensis” | 397-400 |
| Studies from the Morphological Laboratory, Cambridge. Vol. 4. 1888 | ||
| “Development of the Kidney in its Relation to the Wolffian Body in the Chick” | 390 | |
| Q. J. Micr. Sci. Vol. 20. 1880 | ||
| “Early Development of the Wolffian Duct and Anterior Wolffian Tubules in the Chick; with some Remarks on the Vertebrate Excretory System” | 393, 394, 400 | |
| Q. J. Micr. Sci. Vol. 21. 1881 | ||
| SEMON | “Das Excretionssystem der Myxinoiden” | 400, 419 |
| Festschrift f. Gegenbaur. Leipzig. 1897 | ||
| SEMPER | “Die Stammesverwandschaft der Wirbelthiere und Wirbellosen” | 390, 392 |
| Arbeit. a. d. Zool. Zoot. Inst. Würzburg. Vol. 2. 1875 | ||
| “Das Urinogenitalsystem der Plagiostomen und seine Bedeutung für die übrigen Wirbelthiere” | 390, 392 | |
| Ibid. Vol. 2. 1875 | ||
| SHELDON | “On the Development of Peripatus Nova-Zealandiæ” | 400 |
| Studies from the Morphological Laboratory, Cambridge. Vol. 4. 1889 | ||
| SHERRINGTON | “On the Anatomical Constitution of the Nerves of Muscles” | 267 |
| Journ. of Physiol. Vol. 17. 1894. Proc. of Physiol. Soc. June 23 | ||
| SHIPLEY | 334 | |
| “On some points in the Development of Petromyzon fluviatilis” | 167, 305, 378, 401, 405, 406 | |
| Q. J. Micr. Sci. Vol. 27. 1887 | ||
| v. SMIRNOW | “Ueber die Nervenendigungen in den Nieren der Säugethiere” | 477 |
| Anat. Anzeiger. Vol. 19. 1901 | ||
| SMITH, ELLIOT | 17 | |
| SPANGENBERG | “Zur Kenntniss von Branchipus stagnalis” | 396 |
| Zeitsch. f. wiss. Zool. Vol. 25. 1875 | ||
| SPENGEL | ‘Die Enteropneusten’ | 494 |
| Berlin. 1893 | ||
| STARR | Quoted by Edinger | 265, 266 |
| STUDNIÇKA | “Sur les organes pariétaux de Petromyzon Planeri” | 80, 81, 86 |
| Sitzungsber. d. K. Gesell. d. Wiss. in Prag. 1893 | ||
| “Ueber den feineren Bau der Parietalorgane von Petromyzon marinus” | 81, 86 | |
| Sitzungsber. d. K. böhmischen Gesell. d. Wiss. Prag. 1899 | ||
| TAKAMINE | “The Isolation of the Active Principle of the Supra-renal Gland” | 423 |
| Journ. of Physiol. Vol. 27. Proc. of Physiol. Soc., Dec. 14, 1901 | ||
| TARNANI | “On the Anatomy of the Thelyphonides” | 190, 206-208 |
| Revue des Sciences Naturelles, St. Petersbourg. 1890 | ||
| “Die genitalen Organe der Thelyphonus” | 190, 206-208 | |
| Biol. Centralblatt. Vol. 9. 1889 | ||
| TRAQUAIR | “Report on Fossil Fishes collected by the Geological Survey of Scotland in the Silurian Rocks of the South of Scotland” | 343-345, 350 |
| Trans. Roy. Soc., Edin. Vol. 39. 1899 | ||
| VIALLANES | “Contribution à l’histologie du système nerveux des Invertébrés; la lame ganglionnaire de la Langouste” | 100 |
| Ann. Sci. Nat. Vol. 13 | ||
| VINCENT, SWALE | “The Carotid Gland of Mammalia and its Relation to the Supra-renal Capsule, with some Remarks upon Internal Secretion and the Phylogeny of the latter Organ” | 424 |
| Anat. Anzeiger. Vol. 18. 1900 | ||
| “Contributions to the Comparative Anatomy and Histology of the Supra-renal Capsules” | 424 | |
| Trans. Zool. Soc. Vol. 14. 1897 | ||
| VIRCHOW | “Transformation and Descent” | 479 |
| Journ. of Path. and Bacter. Vol. 1. 1893 | ||
| VOGT | 258 | |
| VÖLCKERS | See Hensen and Völckers. | |
| WAGNER | Quoted by Gaubert | |
| WEISS | “Excretory Tubules in Amphioxus Lanceolatus” | 426 |
| Q. J. Micr. Sci. Vol. 31. 1890 | ||
| WELDON | “On the Supra-renal Bodies of Vertebrates” | 420, 424, 429 |
| Q. J. Micr. Sci. Vol. 25. 1885 | ||
| “Note on the Origin of the Supra-renal Bodies in Vertebrates” | 424 | |
| Proc. Roy. Soc. Vol. 37. 1884 | ||
| WHEELER | “Development of the Urino-genital Organs of the Lamprey” | 402, 405 |
| Zool. Jahrbuch. Vol. 13. 1899 | ||
| v. WIJHE | “Ueber die Mesodermsegmente des Rumpfes und die Entwicklung des Excretionsystems bei Selachiern” | 155-157, 172, 173, 188, 234, 258, 260, 262, 263, 266, 273, 280, 308, 390-393, 397, 400, 406-408, 412 |
| Archiv. f. Mikr. Anat. Vol. 33. 1889 | ||
| “Beiträge zur Anatomie der Kopfregion des Amphioxus lanceolatus” | 410, 426-428 | |
| Petrus Camper. Deel. 1; Aflevering. 2 | ||
| WILLEY | See Lankester and Willey. | |
| WOLFF | “Die Cuticula der Wirbelthierepidermis” | 302 |
| Jen. Zeitsch. f. Naturwissenschaft. Vol. 23. 1889 | ||
| WOODWARD, H. | “A Monograph of the British Fossil Crustacea, belonging to the order Merostomata” | 235-240, 249, 251, 275 |
| Palæontographical Society. 1878 | ||
| WOODWARD, SMITH | 339 | |
| ‘Catalogue of Fossil Fishes in the British Museum.’ Part II. | 29, 326, 327, 344, 349, 351 | |
| London. 1891 | ||
| v. ZITTEL | Handbuch der Palæontologie | 190 |
GENERAL INDEX
[The numbers in dark type refer to illustrations]
Acilius larva, eye of, 78, 83
Acromegaly, 425
Actinotrocha, 438
Addison’s disease, 423
Adelopthalmus, 249
Adrenalin, 423, 491
Adrenals, 423, 491
Agnathostomatous fishes, 29, 343
Alimentary canal, 433
Alim”ntary c”nal, Ammocœtes, 168, 405, 445
Alim”ntary c”nal, invertebrate, compared to tube of central nervous system of vertebrate, 43, 433
Alim”ntary c”nal, innervation of, 447
Alim”ntary c”nal, origin of, 444
Alim”ntary c”nal, position of vertebrate and invertebrate, 10
Alim”ntary c”nal, possibility of formation of new, 58
Alim”ntary c”nal, relationship between notochord and, 434
Ammocœtes, 32, 245
Ammo”œtes, an ancestral type, 35, 309
Ammo”œtes, alimentary canal, 168, 405, 445
Ammo”œtes, auditory organ, 378, 379
Ammo”œtes, brain, 39, 40, 41, 45, 46, 48, 54, 61
Ammo”œtes, branchial appendages, 161, 162, 163, 164
Ammo”œtes, bra”chial basket-work, 126, 128, 296, 331, 335
Ammo”œtes, bra”chial chamber, 161, 168, 162, 163
Ammo”œtes, bra”chial circulation in Limulus and, 174
Ammo”œtes, bra”chial diaphragms, 161, 167
Ammo”œtes, bra”chial lamellæ, 175
Ammo”œtes, bra”chial muscles, 171
Ammo”œtes, bra”chial nerves, 164
Ammo”œtes, bra”chial segments, 178, 312
Ammo”œtes, cartilage, hard, 133, 133, 293, 294, 377
Ammo”œtes, cart”lage, muco, 130, 131, 291, 293, 294, 296, 330, 331, 333, 334, 335, 338
Ammo”œtes, cart”lage, soft, 129, 130, 293, 294, 296, 335
Ammo”œtes, degeneracy, evidence of, 59, 94, 343
Ammo”œtes, development, 228, 458
Ammo”œtes, digestion, 58, 442
Ammo”œtes, epithelial cells of gills, 214
Ammo”œtes, epithelial cells of skin, 347
Ammo”œtes, epit”elial pits, 173, 200
Ammo”œtes, eye, 93
Ammo”œtes, e”e, muscles, 267
Ammo”œtes, e”e, median or pineal, 63, 75, 76, 77, 78, 80, 85, 86
Ammo”œtes, e”e, me”ian or pi”eal left, 78, 79
Ammo”œtes, fat-column, 181, 182
Ammo”œtes, f”t in degenerated muco-cartilage, 333, 334
Ammo”œtes, ganglia in embryo, 229, 283
Ammo”œtes, gland-tissue round the brain, 209, 210, 379
Ammo”œtes, head-region, 128, 162, 163, 193, 293, 294, 296, 298, 335
Ammo”œtes, head-shield, 329, 331, 338
Ammo”œtes, liver, 442, 452
Ammo”œtes, lymphatic glandular tissue, 426
Ammo”œtes, Müllerian fibres, 489
Ammo”œtes, muscles, eye, 173, 267
Ammo”œtes, mu”cles, lip, lower, 297
Ammo”œtes, mu”cles, li”,| upper, 305
Ammo”œtes, mu”cles,| respiratory, 171
Ammo”œtes, mu”cles,| somatic, 332, 336, 409
Ammo”œtes, mu”cles,| tubular, 173, 298, 309
Ammo”œtes, nerves, cranial, 141
Ammo”œtes, ne”ves, facial, 186, 311
Ammo”œtes, ne”ves, glossopharyngeal, 186
Ammo”œtes, ne”ves, optic, 105
Ammo”œtes, ne”ves, trigeminal, 282, 288, 288
Ammo”œtes, ne”ves, vagus, 153, 173, 186
Ammo”œtes, nerve-fibres, medullation of, 20
Ammo”œtes, notochord, 182, 435
Ammo”œtes, olfactory tube, 219, 225, 227, 317
Ammo”œtes, oral chamber, 317, 243, 287, 458
Ammo”œtes, parasitism, 60, 286
Ammo”œtes, pituitary, 321
Ammo”œtes, prosomatic region, 243
Ammo”œtes, pronephric duct, 402, 405
Ammo”œtes, relationship to Ostracodermata, 326, 338, 344, 414, 416
Ammo”œtes, retina, 93, 111
Ammo”œtes, skin, 58, 346, 348, 442
Ammo”œtes, skeleton, 125, 126, 132, 291, 296, 335
Ammo”œtes, segments, comparison with segments of Eurypterus, 323
Ammo”œtes, segm”nts, facial, 201
Ammo”œtes, segm”nts, hyoid, 186, 201
Ammo”œtes, segm”nts, prosomatic, 286
Ammo”œtes, septa between myomeres, 416
Ammo”œtes, tentacles of upper lip, 303
Ammo”œtes, test, biological, to show relationship with Limulus, 493
Ammo”œtes, thyroid, 192, 194, 196, 205, 213, 430
Ammo”œtes, transformation, 18, 59, 125, 168, 193, 199, 200, 220, 227, 228, 287, 291, 304, 307, 309, 331, 336, 347, 349, 389, 445
Ammo”œtes, velum, 228, 289, 298, 302
Amœbocytes, 473
Amphibia, 23, 345
Amphioxus, 33, 407
Amphi”xus, atrial cavity, 409
Amphi”xus, branchial nephric glands, 426
Amphi”xus, endostyle, 198, 212
Amphi”xus, excretory organs, 389, 395, 477
Amphi”xus, neuropore, 220, 457
Amphi”xus, notochord, 435, 436, 443
Amphi”xus, pleural folds, 495
Amphi”xus, septa between myomeres, 416
Amphi”xus, somatic muscles, 409
Amphi”xus, yolk, 485
Androctonus, 53, 54, 372, 423
Annelids, lateral sense-organs, 357, 367
Ann”lids, nephric organs, 390
Ann”lids, rigin of Arthropods from, 395
Ann”lids, parapodal ganglia, 283
Ann”lids, phagocytic glands, 421
Anthozoa, 474
Antiarcha, 29, 326, 343
Antibody, 492
Antitoxin, 492
Anus, 43, 457
Aponeuroses, 327, 342, 414
Apparatus, auditory, 355
Appa”rtus, dioptric, 83
Appa”rtus, respiratory, 148
Appa”rtus, suctorial, of Petromyzon, 287
Appendages, branchial, of Ammocœtes, 161, 162, 163, 164
Appe”dages, bra”chial, of Limulus, 164
Appe”dages, bra”chial, of internal, 149
Appe”dages, derivation of suctorial apparatus of Petromyzon from, 290
Appe”dages, disappearance of, in transformation of Arthropod into Vertebrate, 386, 413
Appe”dages, evidence of, in prosomatic region of ancient fishes, 342
Appe”dages, muscles, in Limulus and Scorpion, 247
Appe”dages, prosomatic, of Gigantostraca, 234
Appe”dages, Trilobites, 351
Apus, 28, 137, 436, 437
Arachnids, eyes, 75, 87
Arac”nids, diverticula of stomach, 109
Arac”nids, lyriform organs, 364, 368
Arac”nids, segmental excretory organs, 423
Archæocytes, 473
Artemia, v. Branchipus
Arthropleura, 249
Arthropoda, arrangement of organs, 10
Arthr”poda, evolution, 11
Arthr”poda, excretory organs, 396, 418
Arthr”poda, eyes, 75, 89
Arthr”poda, giant-fibres, 489
Arthr”poda, musculature, 411
Arthr”poda, olfactory organs, 220
Arthr”poda, resemblance to ancient fishes, 29
Astacus, brain, 54
Ast”cus, digestive ferment in cells lining the carapace, 442
Ast”cus, optic chiasma, 101
Ast”cus, optic stalk, 91
Ast”cus, etina, 98
Asterolepis, 326, 342
Atrium, 410
Auchenaspis (Thyestes), 30, 31, 75, 275, 326, 327, 328, 338
Auditory apparatus, 355
Auerbach, plexus of, 447
Aurelia, 475
Autonomic nerves, 3
Balanoglossus, 12, 12, 433, 438, 494
Bdellostoma, 394, 405
Belinurus, 24, 249, 351
Bird, rhomboidal sinus, 46
Bladder, 449
Bla”der, swim, 148
Blastula, 459, 471, 473
Blood, 463, 472, 474
Bl”od, circulation, in Ammocœtes and Limulus, 174
Bl”od, secretion of ductless glands into, 418
Bothriolepis, 29, 32, 239, 326, 351, 450
Bone, 344, 474, 481
Brain, Ammocœtes and Arthropod, 54, 61
Br”in, and brain-case of Ammocœtes, 40, 41, 46, 209
Br”in, caudal, of Thelyphonus, 450
Br”in, epithelial lining of, 38
Br”in, roof, 39
Br”in, Sphæroma serratum, 62, 90
Br”in, Thelyphonus, 56
Br”in, ventricles, 4
Br”in, vesicles, 48
Branchial basket-work of Ammocœtes, 126, 128, 296, 331, 335
Branchipus, 28
Bran”hipus, brain, 51, 54
Bran”hipus, eyes, lateral, 88
Bran”hipus, e”es, lat”ral, retina of, 91, 97
Bran”hipus, e”es, median, 75
Bran”hipus, excretory organs, 396
Bran”hipus, (Artemia) diverticula of gut and retinal ganglion, 110, 111, 113
Bran”hipus, nerves of appendages, 157
Bran”hipus, segmentation, 159
Bran”hipus, resemblance to Trilobite, 436
Bunodes, 24, 30, 249, 341, 351, 414
Bundle of Meynert, 48, 77
Bundles, posterior longitudinal, 489
Buthus, muscles, 270
Calcification in aponeuroses of Cephalaspis, 414
Calcifi”ation cartilage, 140,330
Calcifi”ation successive layers of the skin, 348
Camerostome, 221, 222, 223, 224, 241, 271
Canal, alimentary, formation of vertebrate, 58, 433, 446
Ca”al, alime”tary, innervation, 447
Ca”al, alime”tary, relationships between notochord and, 434
Ca”al, alime”tary, origin, 444
Ca”al, Haversian, 329
Ca”al, central, of spinal cord, 405, 439, 455
Ca”al, spinal, 182
Capsule, auditory, 377, 379
Cartilage Ammocœtes, muco, 127, 130, 131, 200, 291, 303, 330, 333, 334, 344
Cart”ilge Ammo”œtes, hard, 133, 133, 377
Cart”ilge Ammo”œtes, soft, 126, 129, 130
Cart”ilge Ammo”œtes, spinal cartilages, 414
Cart”ilge Hypoctonus, 133, 142
Cart”ilge Limulus, hard, 142
Cart”ilge Lim”lus, muco, 139
Cart”ilge Lim”lus, soft, 20, 130, 137
Cart”ilge origin, 474, 481
Cart”ilge staining reactions, 131, 133, 139, 330, 336
Cavity, atrial, 409, 413
Cai”ty, cœlomic, 167, 251, 266, 320, 389, 391, 408, 422, 430, 472
Cells, free-living, 463
Centre, vaso-motor, 468
Cephalaspis, diverticula of gut, 109
Ceph”laspis, eyes, lateral, 75, 275
Ceph”laspis, e”es, median, 75
Ceph”laspis, head-shield, 327, 328, 330, 338
Ceph”laspis, muscles on head-shield, 269
Ceph”laspis, resemblance to Ammocœtes, 145, 291, 326, 329, 338, 348, 414
Ceph”laspis, resem”lance to Arthropod, 29
Ceph”laspis, segmentation, 339
Ceratodus, 148
Cephalization, 51
Cephalodiscus, 438
Cephalopod, 23
Cerebellum, 47, 50
Chætopoda, 395
Chamber, oral, of Ammocœtes, 243, 287, 458
Cheliceræ, 235
Chiasma, optic, 101
Chilaria, 235, 238, 291, 301, 458
Chitin, 85, 119, 139, 205, 206, 302, 329, 346, 359, 440, 443
Cilia, 206
Circulation, branchial, 174
Cirri, 357
Clarke’s column, 467
Clepsine, nephridial glands, 423
Cochlea, 378
Cœlenterata, 465, 472
Cœlolepidæ, 344
Cœlom, 167, 251, 400, 472, 481
Cœlomata, 472
Cœlomocœla, 472, 475
Cœlomostomes, 477, 481
Colleneytes, 474
Commissure, anterior, 49
Comm”ssure, œsophageal, 14
Comm”ssure, posterior, 48, 280
Comparison of brains of Ammocœtes and Arthropod, 61
Comp”rison of br”ins of invertebrate from Branchipus to Ammocœtes, 54
Comp”rison of br”ins of vertebrate, 40
Comp”rison of branchial circulation in Ammocœtes and Limulus, 174
Comp”rison of bran”hial lamellæ of Scorpion and Ammocœtes, 175
Comp”rison of bran”hial segments of Ammocœtes and Petromyzon, 169
Comp”rison of Cephalaspidian and Palæostracan fish, 31
Comp”rison of Cœlom of Peripatus and Vertebrate, 400
Comp”rison of dermal covering of Pteraspis with chitin of Limulus or dentine of fish scales, 346
Comp”rison of entosternite or plastron of Limulus with trabeculæ of Ammocœtes, 145
Comp”rison of excretory organs of vertebrates and invertebrates, 389
Comp”rison of gut of Arthropod and tube of central nervous system of Vertebrate, 43, 244, 433, 440, 455, 457
Comp”rison of head-shield of Cephalaspis and Ammocœtes, 291, 329, 338
Comp”rison of hypophysial tube with olfactory tube of Arthropod ancestor, 229
Comp”rison of hypop”ysial t”be with position of palæostoma, 317
Comp”rison of mesosomatic region of Ammocœtes and Eurypterus, 192
Comp”rison of muscles, branchial, of Ammocœtes and appendage muscles of Scorpion, 171, 447
Comp”rison of mu”cles, eye, of Vertebrate with dorso-ventral muscles of Scorpion, 267, 272, 459
Comp”rison of mu”cles, of oral chamber of Ammocœtes and prosomatic musculature of Limulus, 247, 447
Comp”rison of mu”cles, longitudinal body-muscles of Vertebrate and dorsal longitudinal muscles of Arthropod, 411, 447
Comp”rison of nerves, appendage of Limulus and Branchipus to lateral root system of Vertebrate, 157
Comp”rison of ne”ves, cranial and spinal segmental, 152
Comp”rison of nervous systems of Vertebrate and Arthropod, 36
Comp”rison of pineal gland of vertebrates and median eyes of Arthropod, 63, 456
Comp”rison of pituitary body and coxal glands, 246, 319, 321
Comp”rison of prosoma and mesosoma of Limulus and Ammocœtes, 140, 141
Comp”rison of prosomatic region of Ammocœtes and Eurypterus, 244, 333
Comp”rison of retina in Ammocœtes and Musca, 97
Comp”rison of re”ina compound in Arthropod and Vertebrate, 87
Comp”rison of skeleton of Limulus and Ammocœtes, 126, 136
Comp”rison of sense-organs of Arthropod appendages with auditory organs of Vertebrate, 375
Comp”rison of thyroid with endostyle, 198
Comp”rison of thy”oid w”th uterus of Scorpion, 205
Corneagen, 69
Corpora quadrigemina, 47
Corpuscles, Pacinian, Herbst, Grandry, etc., 470
Coxal glands, 242, 246, 319, 321, 389, 398, 403, 429
Cranium, 121, 145, 339
Crayfish, 442, 489
Crest, neural, 281
Cromatophores of frog, 470
Crura cerebri, 14
Crustacea, first appearance, 27
Crust”cea, eyes, 76, 87
Crust”cea, retina, 100
Crust”cea, segmental glands, 422
Ctenophora, 474
Cyathaspis, 29, 326, 340, 343
Cyclostomata, 165, 229, 343, 353, 424
Cysts, 50
Daphnia, 112
Degeneration, 17, 19, 59, 74, 78, 94, 107, 212, 309, 333, 336, 343
Deiters’ nucleus, 489
Dendrites, 72
Development, parallel, 497
Devel”pment, of two types of eye, 73
Devel”pment, vertebrate retina, 101
Diaphragms, 161, 167
Didymaspis, 327, 338
Digestion, 441
Dinosaurs, 17
Dipnoans, 23, 45, 148
Diptera, 89, 369
Diverticula, optic, 102
Dogfish, skull, 121, 123
Drepanaspis, 344, 345, 450
Drepanopterus Bembycoides, 238
Ectognath, 238, 242, 271, 304, 342, 381
Eel, 488
Elasmobranchs, 23, 343, 423
Elastin, 435
Embryo, head of dogfish, 121, 123
Em”ryo, skull of pig, 121
Embryology, principles of, 455
Encepalomeres, 262
Endognath, 238, 271, 304, 381
Endostoma, 241, 306
Endostyle, 198, 212
Entapophysis of Limulus, 139
Enterocœla, 472
Enteropneusta, 438, 494
Entochondrites, 377
Entosclerite, 222, 271
Entosternite, 143
Epiblast, 444, 445, 459
Epithelium cells of Ammocœtes, 347
Epith”lium of central nervous system of vertebrates, 38, 457
Epith”lium of cœlomic spaces in annelids, 421
Epith”lium of optic diverticula, 103
Epith”lium of peritoneal, pleural, and pericardial cavities, 477
Epith”lium of velum of Ammocœtes, 301, 302
Equilibration, 358
Eukeraspis, 326
Eurypterus, 26, 150, 191, 237
Eury”terus, appendages, 150, 236, 237
Eury”terus, classification, 249
Eury”terus, comparison with Ammocœtes, 170, 323
Eury”terus, diagram of sagittal median section, 240, 245
Eury”terus, endostoma, 241, 306
Eury”terus, eyes, 275
Eury”terus, mesosomatic segments, 192
Eury”terus, muscles of carapace, 269
Eury”terus, operculum, 150, 190, 212
Evidence of alimentary canal, innervation, 446
Evide”ce of auditory apparatus and lateral line organs, 355
Evide”ce of cœlomic cavities in Limulus, 251
Evide”ce of degeneracy in Ammocœtes, 59, 94, 343
Evide”ce of embryology, cartilage, 20, 129
Evide”ce of embry”logy, eye-muscles, 263
Evide”ce of embry”logy, excretory organs, 390
Evide”ce of embry”logy, heart, 179, 451
Evide”ce of embry”logy, nervous system, central, cerebral vesicles, 48, 458
Evide”ce of embry”logy, ner”ous sy”tem, ce”tral, epithelial tube, 37, 42, 102, 244, 433, 455
Evide”ce of embry”logy, ner”ous sy”tem, ce”tral, neurenteric canal, 37
Evide”ce of embry”logy, ner”ous sy”tem, ce”tral, neuropore, 220, 457
Evide”ce of embry”logy, ner”ous sy”tem, ce”tral, optic diverticula, 102
Evide”ce of embry”logy, ner”ous sy”tem, ce”tral, spinal cord, 46
Evide”ce of embry”logy, oral chamber, 228, 242, 243, 290
Evide”ce of embry”logy, olfactory organ, 220, 227
Evide”ce of embry”logy, palæostoma or old mouth, 317
Evide”ce of embry”logy, pineal or median eyes, 15, 63, 74, 456
Evide”ce of embry”logy, pituitary body and coxal glands, 246, 319
Evide”ce of embry”logy, thyroid, 192, 194
Evide”ce of embry”logy, segmentation, double, of head, 157, 234, 258
Evide”ce of embry”logy, skeleton, cranial, 120, 153
Evide”ce of nervous system, central, 8
Evide”ce of notochord, origin from segmented region, 443
Evide”ce of olfactory apparatus, 218
Evide”ce of organs of vision, 68
Evide”ce of palæontology, 20, 497
Evide”ce of pineal or median eyes, 74
Evide”ce of prosomatic musculature, 247
Evide”ce of respiratory apparatus, 148
Evide”ce of segmentation in head-shield, 339
Evide”ce of skeleton, 119
Evolution, 8, 15, 20, 149, 482, 497
Evol”tion, of brain in brain-case, 210
Evol”tion, of cranium of Vertebrate, 342
Evol”tion, of excretory organs, 389
Evol”tion, of eye of Vertebrate, 114
Evol”tion, of nervous system, central, 34
Evol”tion, of tissues, 19
Evol”tion, of Vertebrate from Balanoglossus and Amphioxus, 33
Eyes, 68
Ey”s, lateral, 87, 105, 108
Ey”s, median or pineal, 74, 77, 78, 79
Fat-cells in muco-cartilage, 332
Fat-column of Ammocœtes, 181, 182
Fibres, Mauthnerian, 488
Fib”rs, Müllerian, of Ammocœtes central nervous system, 489
Fib”rs, Müll”rian, of retina, 96, 107
Fishes, classification, 218
Fis”es, ancient, classification, 326, 343
Fis”es, ani”ent, cloacal region, 450
Fis”es, ani”ent, dominance, 23
Fis”es, ani”ent, eyes, 75
Fis”es, ani”ent, head-shields. See Head-shields
Fis”es, ani”ent, pleural folds, 414
Fissure, posterior, 43
Fittest, survival of, 16, 34
Flabellum, 359, 360, 362, 363, 366
Folds, pleural, 410, 414
Function of auditory organ, double, 358
Funt”ion of lateral line sense-organs, 357
Funt”ion of nerves, 448
Funt”ion of thyroid, 212, 215
Fusion of ganglia, 52
Galeodes, 230
Gale”des, brain, and camerostome, 222, 223
Gale”des, primordial cranium, 341
Gale”des, racquet-organs, 369, 375
Ganglia, infraœsophageal, 4, 12, 14, 51, 221
Ganl”ia, supraœsophageal, 4, 12, 14, 49, 52, 221, 225
Ganl”ia, origin of, of cranial and spinal nerves, 281
Ganglion, epibranchial, 164, 282
Ganl”ion, habenulæ, 48, 78
Ganl”ion, optic of retina, 72, 89, 97
Ganl”ion, of posterior root, 466
Ganl”ion, cells of sympathetic system, 424, 428, 448
Ganoids, 23, 345
Gastrula theory, 165, 459
Genital corpuscles, 470
Geological record, 20
Geol”gical strata, 22
Geotria australis, 80
Germ-band, 482
Germ-cells, 471
Giant-fibres, 489
Gigantostraca, 25, 234
Gills, 148, 161, 185, 214, 494
Glabellum, 339
Glands, carotid, 427
Gla”ds, coxal, 242, 246, 319, 321, 425, 429
Gla”ds, ductless, 418
Gla”ds, generative, of Limulus, 209
Gla”ds, internal secretion of, 214
Gla”ds, lymphatic, 418
Gla”ds, pineal, 15, 63, 75, 456
Gla”ds, pituitary, 244, 246, 319, 425
Gla”ds, segmental, of Crustacea, 422
Gla”ds, submaxillary, 466
Gla”ds, sweat, 448
Gla”ds, thymus, 425
Gla”ds, thyroid, of Ammocœtes, 193, 194, 196, 201, 205, 429
Gla”ds, tissue round brain of Ammocœtes, 209, 379
Gla”ds, uterine, of Scorpion, 202, 203, 204, 205
Gnathostomata, 60, 343
Goblet, 359, 360, 373
Goitre, 215
Gonad, 475, 479
Gonocœle, 475, 481
Grooves, ciliated, 188, 197, 212
Gro”ves, hyper-pharyngeal of Amphioxus, 410
Gro”ves, ventral, of apus and trilobites, 436
Gymnophiona, 393
Hæmocytes, 472
Head of embryo dogfish, 121, 123
Head-shield, dorsal, of Ammocœtes, 330, 331, 338
Head-s”ield, dor”al, of Auchenaspis, 29, 31, 338
Head-s”ield, dor”al, of Cephalaspis, 327, 328, 330, 338, 348
Head-s”ield, dor”al, of Cyathaspis, 340
Head-s”ield, dor”al, of Didymaspis, 338
Head-s”ield, dor”al, of evidence of segmentation, 339
Head-s”ield, dor”al, of Keraspis, 328
Head-s”ield, dor”al, of Ostreostraci, 327, 348
Head-s”ield, dor”al, of Palæostracan, 348
Head-s”ield, dor”al, of Pteraspis, 29
Head-s”ield, dor”al, of Thyestes, 29, 31, 327, 332, 338, 340, 341, 348
Head-s”ield, ventral, Scaphaspis, 349
Heart, nerves, 2, 447
Her”t, origin of vertebrate, 179, 451, 459
Her”t, relative position in vertebrate and invertebrate, 175
Her”t, veins forming vertebrate, 180
Hemiaspis, 24, 25, 249, 250, 351, 414
Hemispheres, cerebral, 47
Hepatopancreas of Ammocœtes, 452
Hepatop”ncreas of Limulus, 211
Heterostraci, 29, 275, 326, 343
Hirudinea, 478
Histolysis in transformation of the lamprey, 59
Homology of branchial region of vertebrate and invertebrate, 149
Homol”gy of ductless glands and nephridial organs, 418
Homol”gy of external genital ducts of arthropods and nephridia of annelids, 429
Homol”gy of germinal layers in all Metazoa, 459
Homol”gy of pituitary body of Ammocœtes and coxal glands of Limulus, 319
Homol”gy of tubular muscles of Ammocœtes and veno-pericardial muscles of Limulus, 309
Homol”gy of ventral aorta of vertebrate and longitudinal venous sinuses of Limulus, 178
Hydra, 441, 465, 472, 476
Hydrophilus larva, eye, 84
Hyoid segment in Ammocœtes, 186, 267
Hypoblast, 434, 438, 444, 445, 459
Hypoctonus, cartilage cells in entosternite, 133
Hypo”tonus, operculum, 189, 207
Hypogastric plexus, 3
Hypogeophis, 393
Hypophysis, 229, 244, 317, 318, 340
Infundibulum, position, 122,132
Infun”ibulum, tube, the ancestral œsophagus, 4, 37, 244, 318
Infun”ibulum, tu”e, relation to neural canal, 14, 36, 318, 440, 457
Infun”ibulum, tu”e, relati”n to notochord, 318, 435,440
Infun”ibulum, tu”e, relati”n to olfactory tube, 220, 228, 318, 340
Insects, chordotonal organs, 364, 370
Invertebrate, heart, 175, 179
Invert”brate, excretory organs, 418
Invert”brate, nervous system, 13, 54
Invert”brate, segmental nerves, 152
Keraspis, 75, 328, 338
Kidney, 420, 459, 476
Kid”ey, nerves, 477
King-crab, v. Limulus
Labyrinthodont, 21, 28
Lamina terminalis, 49
Lamprey, v. Ammocœtes and Petromyzon
Larva, v. Transformation of the Lamprey
Lateral line system, 261, 355, 411, 470
Law of Progress, 19
Lw” of Recapitulation, 434, 456, 498
Layer, germinal, 459
Lay”r, laminated, 347, 348
Leech, 421
Lens, formation, 83, 115
Lepidosiren, 148, 461, 466
Limulus or king-crab, 25, 140, 236, 240
Liml”us appendages, branchial, 138, 164, 175
Liml”us appendages, prosomatic, 381
Liml”us brain, 54
Liml”us circulation, 174, 176
Liml”us classification, 26, 249
Liml”us cœlomic cavities, 252, 328
Liml”us coxal glands, 321, 389, 397, 403, 429
Liml”us eyes, median, 62, 74, 81
Liml”us entosternite or plastron, 142, 143
Liml”us flabellum, 360, 362, 363, 380, 381
Liml”us generative organs and ducts, 189, 202, 208, 209, 380
Liml”us heart, 180
Liml”us musculature, branchial, 170
Liml”us muscl”ature, prosomatic, 247
Liml”us muscl”ature, veno-pericardial, 177, 297, 309, 313
Liml”us nerves, appendage, 140, 157
Liml”us ner”es, cardiac, 314
Liml”us ner”es, segmental, tripartite division of, 157, 235, 267, 355
Liml”us segments, branchial, 152
Liml”us segm”nts, first mesosomatic, 188
Liml”us segm”nts, prosomatic, 233
Liml”us operculum, 189, 202, 235, 295
Liml”us sense-organs, poriferous, of appendages, 359
Lip, lower, of Ammocœtes, 246, 289, 297, 458
Li”, upper, of Am”ocœtes, 228, 243, 303, 336
Liver, Ammocœtes, 452
Liv”r, Limulus, 209, 211
Lizard, pineal eye, 80
Liz”rd, suprarenals, 424
Liz”rd, tail, 50
Lobes, optic, 101
Lobster, 489
Lungs, 148
Lung-books of scorpions, 150
Lymph, 474
Lymph-corpuscles, 463, 490
Lymphocytes, 472
Malapterurus, 470
Mammal, dominance of, 21
Man, dominance of, 17
Marsipobranchs, 23, 35
Medullation of nerve-fibres, 20, 267, 467, 477
Membranes, basement, 436
Meroblastic egg, 485
Merostomata, 25, 249, 321
Mesencepalon, 48
Mesoblast, 444, 455, 459
Mesoglœa, 474
Mesonephros, 389, 400, 424, 429
Mesosoma, 52
Mesothelium, 472, 477
Metanephros, 389
Metasoma, 52, 387, 411
Metastoma, 239, 246, 272, 289, 342, 458
Metazoa, 444, 459, 471, 472
Meynert’s bundle, 48, 77
Mollusca, dominance of, 23
Mouth, old, or palæostoma, 14, 317, 322, 440, 458
Mo”th, vertebrate, 317
Muco-cartilage, v. Cartilage
Muscles, antagonistic, 447
Mus”les, branchial, 170
Mus”les, connection of, with central nervous system, 464
Mus”les, eye, and their nerves, 263
Mus”les, prosomatic, 243, 247
Mus”les, phylogeny of origin of skeletal, 478
Mus”les, rudimentary, in Ammocœtes, 289
Mus”les, somatic trunk, origin of, 406
Mus”les, striated, 20, 155
Mus”les, tubular, of Ammocœtes, 309
Mus”les, unstriped, 20, 447, 491
Mus”les, visceral and parietal, 155, 172
Mus”les, veno-pericardial of Limulus and Scorpion, 177, 297, 309
Muscle-spindles, 267
Mygalidæ, stomach, 109
Mygl”idæ, segmentation, 249, 306
Myomeres, 262, 337, 414, 479
Myotomes, 332, 337, 338, 391, 407, 408
Mysis, eyes, 100
My”is, ductless glands, 422
Myxine, 220, 392, 402, 419
Nebalia, 144, 422
Nemertina, 475
Nephridia, 395, 421, 429
Nephrocœle, 430
Nephrotome, 393
Nerves, abducens, 155, 263, 266
Ner”es, auditory, 356, 376
Ner”es, autonomic, 3
Ner”es, facial, 155, 156, 186, 188, 192, 311, 356, 378
Ner”es, fa”ial, ramus branchialis profundus, 311
Ner”es, to flabellum, in Limulus, 361, 375
Ner”es, glossopharyngeal, 155, 156, 186, 356
Ner”es, hypoglossal, 156
Ner”es, inhibitory, 447
Ner”es, inedullation of, 20, 267, 467, 477
Ner”es, occulomotor, 155, 234, 263, 274
Ner”es, olfactory, 229
Ner”es, optic, 101, 104
Ner”es, ot”ic, of pineal eye, 79
Ner”es, origin of ganglia of cranial and spinal, 281
Ner”es, to pecten of Scorpion, 375, 376
Ner”es, preganglionic, 2
Ner”es, of prosoma in Limulus, 235, 355
Ner”es, regeneration of, 469
Ner”es, roots, of Limulus, 157
Ner”es, sacral, 448
Ner”es, segmental, 152, 156
Ner”es, segmental nature of cranial, 259, 411
Ner”es, spinal, absence of lateral roots in, 388
Ner”es, spinal accessory, 154
Ner”es, trigeminal, 151, 155, 156, 234, 243, 257, 279
Ner”es, trigm”inal, motor nucleus of, 280
Ner”es, trigm”inal, of Ammocœtes, 288
Ner”es, tripartite arrangement of cranial nerves, 154, 157, 235, 267, 355
Ner”es, trochlear, 48, 155, 234, 263, 276
Ner”es, vagus, 151, 154, 156, 173, 186, 356, 447, 449
Nervous system, central, comparison of Vertebrate and Arthropod, 36, 457
Nervous “ystem, ce”tral, connection of, with muscular and epithelial tissues, 464
Nervous “ystem, ce”tral, conne”tion of, with retina, 71
Nervous “ystem, ce”tral, disease of, 50
Nervous “ystem, ce”tral, evidence of, 8
Nervous “ystem, ce”tral, evolution of, 34
Nervous “ystem, ce”tral, importance of, 16, 463, 482, 498
Nervous “ystem, ce”tral, invertebrate, 10, 13, 54
Nervous “ystem, ce”tral, origin of, 480
Nervous “ystem, ce”tral, relation of germ-band to, 483
Nervous “ystem, ce”tral, segmentation of vertebrate, 51
Nervous “ystem, ce”tral, tube of, 36-51, 102, 211, 433, 455, 457
Nervous “ystem, ce”tral, vertebrate, 10, 13, 40, 41, 152
Nervous “ystem, enteric, 447
Nervous “ystem, sympathetic, 2, 424, 428, 448, 491
Neurenteric canal, 37
Neuroblast, 465
Neuromeres, 55, 247, 262, 312, 316
Neurones, 72, 92, 465
Neuropil, 71, 91
Neuropore, 220, 457
Nose, 219
No”e, of Osteostraci, 329, 352, 458
Notochord, 120, 122, 180, 181, 220, 244, 295, 318, 405, 417, 433, 436, 494
Ocelli, 70
Œsophagus of Ammocœtes, 405
Œsop”agus of Arthropod, compared to tube of infundibulum, 4, 244, 440
Olfactory apparatus, evidence of the, 218
Olfa”tory organs of the Scorpion group, 220
Olfa”tory tube of Ammocœtes, 219, 225, 244, 317
Oligochæta, 421, 478
Operculum of Eurypterus, 191, 212, 291
Operc”lum of Limulus, 189, 202, 235, 295
Operc”lum of Phrynus, 191
Operc”lum of Scorpion, 189, 206, 212, 372
Operc”lum of Thelyphonus, 189, 190, 206
Organs, arrangement of, 10
Org”ns, auditory, of arachnids and Insects, 368
Org”ns, branchial, innervation of vertebrate, 151
Org”ns, bran”hial, sense-organs of embryo vertebrate, 261, 281
Org”ns, chordotonal, of insects, 364, 369, 370
Org”ns, electric, 470
Org”ns, generative, of Limulus, 208, 209
Org”ns, gener”tive, connection between Thyroid gland and, 215
Org”ns, genital, of sea-scorpions, 206
Org”ns, lateral line, 355, 411
Org”ns, lyriform, of arachnids, 364, 369
Org”ns, olfactory, of Scorpion group, 220
Org”ns, phagocytic, 420
Org”ns, racquet, of Galeodes, 369, 375
Org”ns, segmental excretory, 389, 391, 408, 418, 459, 477
Org”ns, sense, of appendages of Limulus, 358
Org”ns, vestigial, 456
Org”ns, of vision, evidence of, 68
Org”ns, vital, 57
Origin of alimentary canal, 444
Ori”in of arthropods from annelids, 395
Ori”in of atrial cavity, 409
Ori”in of auditory capsules and parachordals, 377
Ori”in of cœlom, 475, 481
Ori”in of ductless glands, 428
Ori”in of free cells, 472
Ori”in of heart of vertebrate, 179
Ori”in of lateral line organs, 356
Ori”in of muscles, 478
Ori”in of musculature, branchial, 170
Ori”in of muscul”ture, somatic trunk, 406
Ori”in of nervous system, central, 480
Ori”in of notochord, 434
Ori”in of segmental excretory organs, 389
Ori”in of skeleton of vertebrates, 119
Ori”in of vertebrates, 9, 36, 351, 433, 493
Ostracodermata, 326, 343
Osteostraci, 29, 75, 275, 326, 343
Otoliths, 378
Ovum, 473
Pacinian bodies, 470, 477
Palæmon, 20, 422
Palæontology, evidence of, 20, 497
Palæostoma, 317
Palæostraca, 27, 396
Palæo”traca, median eyes, 74
Palæo”traca, mesosomatic appendages, 188
Palæo”traca, olfactory organs, 221
Palæo”traca, segments, compared to Ammocœtes, 308
Pantopoda, glands, 423
Parachordals, 121, 132, 377
Parapodia, 357
Parapodopsis, foot glands, 422
Parathymus, 427
Parathyroids, 427
Parietal organ, 76
Pecten of scorpion, 114, 359, 366, 371, 372, 373, 374
Pedipalpi, 190
Periblast, 471
Peripatus, 396, 399, 400, 411, 421, 429
Petromyzon, alimentary canal, 405, 445
Petro”mzon, auditory organ, 378
Petro”mzon, branchial segments, 169
Petro”mzon, life-history, 59
Petro”mzon, olfactory tube, 219, 226
Petro”mzon, pronephric duct, 402
Petro”mzon, retina and optic nerve, 95
Petro”mzon, skeleton, 125
Petro”mzon, suctorial apparatus, 287, 304
Petro”mzon, transformation, v. Transformation of the Lamprey
Phagocytes, 420, 471
Pharynx of Amphioxus, 410
Phar”nx of Vertebrate, 440
Phoronis, 439
Phrynus, brain, 53
Phry”us, caudal brain, 450
Phry”us, carapace and carapace removed, 250
Phry”us, cœcal diverticula, 109
Phry”us, evidence of segmentation of carapace, 249, 250, 341
Phry”us, operculum, 191
Phry”us, prosomatic appendages, 306
Phry”us, crossing of dorso-ventral muscles, 271, 277
Phry”us, stridulating apparatus, 368
Phyllodoce, 395
Phyllopoda, 321
Pigment, in Ammocœtes, in position of atrial cavity, 412
Pigm”nt, in epithelial lining of central nervous system, 43, 457
Pigm”nt, in choroid of vertebrate eye, 104, 107
Pigm”nt, in between glandular cells round brain of Ammocœtes, 211, 379
Pigm”nt, in tapetal layer of retina, 70
Pigm”nt, in white, of right pineal eye of Lamprey, 76, 80
Pineal body, 14, 15
Pin”al eyes, 74, 233, 244
Pin”al ey”s, of Ammocœtes, 80, 78, 85
Pin”al gland, 63, 75, 456
Pits, epithelial, of diaphragms in Ammocœtes, 164
Pi”t, epith”lial, of skin in Ammocœtes, 173, 200
Pituitary body, 244, 246, 319, 321, 425, 430
Plasma-cells, 471
Plakodes, 283
Planarians, 475
Plastron, formation of cranial walls from the, 86, 322, 341
Plat”ron, of Limulus, 136, 142, 143
Plat”ron, Palæostracan, compared to trabeculæ of Ammocœtes, 145, 377
Plat”ron, muscles attached to the, 270
Plat”ron, of Thelyphonus, 143
Platyhelmia, 475
Pleuron, 410, 415
Plexus, of Auerbach, 447
Plex”s, of choroid, 38, 45, 49, 103
Plex”s, of hypogastric, 3
Polychæta, 357, 395
Pores, abdominal, 430
Porifera, 473
Pouch, formation of gill, 165, 166
Prestwichia, 24, 25, 249, 351
Principle of concentration and cephalization, 51
Prini”ple of embryology, 455
Pristiurus, 424
Progress, law of, 19
Progr”ss, result of, 56
Pronephros, 389, 397, 419, 424, 449
Prosencephalon, 48
Prosoma, 52
Protopterus, 148
Protostraca, 27, 396, 417
Proto”traca, dominance of, 28
Protozoa, 166, 479
Pseudoniscus, 25, 249
Pteraspis, 29, 30, 275, 326, 343, 344, 350
Pterichthys, 29, 31, 239, 326, 351
Pterygoid, pedicle of, 295
Pterygotus, 25, 27, 56, 170, 191, 221, 235, 238, 249, 276
Ptychodera, 494, 495
Ramus branchialis profundus of facial nerve, 311
Ra”ms communicans, 2, 3
Raphe, 46
Recapitulation, law of, 434, 456, 498
Regeneration of nerves, 469
Reptiles, dominance of, 21
Retina, compound, 71
Ret”ia, development of, 101
Ret”ia, inversion of, in Vertebrates, 114
Ret”ia, inverted, 70
Ret”ia, layers of compound, 73
Ret”ia, lay”rs of in Crustacean eye, 100
Ret”ia, of lateral eye of Ammocœtes, 93, 95, 111
Ret”ia, Musca, 89
Ret”ia, Pecten and Spondylus, 114
Ret”ia, upright compound, 72
Ret”ia, upri”ht simple, 69
Rhabdites, 69, 81
Saccus vasculosus, 244, 322
Scales, 345
Scaphaspis, 349
Schwann, sheath of, 469
Sclerotomes, 388
Scorpion, brain, 54
Scor”ion, branchial lamellæ, 175
Scor”ion, development, 482
Scor”ion, entochondrites, 377
Scor”ion, excretory organs, 397
Scor”ion, eyes, 75
Scor”ion, lung-books, 150, 170
Scor”ion, lymphatic glands, 423
Scor”ion, muscles, oblique, 278
Scor”ion, mus”les, recti, 271
Scor”ion, mus”les, respiration, 171
Scor”ion, mus”les, veno-pericardial, 177
Scor”ion, muscular system, 247, 268, 269
Scor”ion, nerves to Cheliceræ, 237
Scor”ion, olfactory organs, 220
Scor”ion, operculum of male, 189, 206, 212
Scor”ion, pecten, 359, 366, 371, 373, 374, 377
Scor”ion, under surface, 372
Scor”ion, uterus, 189, 202, 203, 204, 205, 212
Sea-scorpions, 25, 26, 27, 56, 150, 170, 191, 208, 221, 232, 235, 241, 349, 359
Segmentation, branchiomeric, 124
Segmet”ation, body-muscles in vertebrate, 388
Segmet”ation, eye-muscles, 248
Segmet”ation, of head, double, 155, 157, 173, 234, 258, 411, 459
Segmet”ation, of head-shield, 339
Segmet”ation, history of cranial, 258
Segments, branchial of Ammocœtes, 161, 178, 186
Segm”nts, hyoid, in Ammocœtes, double, 186, 201, 267, 300
Segm”nts, innervation of branchial, 151
Segm”nts, first mesosomatic, in Limulus and its allies, 188
Segm”nts, mesosomatic, of Eurypterus, 192
Segm”nts, prosomatic of Limulus and its allies, 233, 249
Segm”nts, prosm”atic of Ammocœtes, 286
Segm”nts, of spinal region of Vertebrates, 388
Segm”nts, of trigeminal nerve-group, 257, 279
Segm”nts, tubular muscles of hyoid, 299
Sense-organs of Amphioxus, 34
Sense-o”rans of branchial, of Limulus, 359, 360
Sense-o”rans of lateral, of Annelids, 357, 367
Sense-o”rans of lateral-line system, 356, 411, 470
Serum, 492
Significance of the optic diverticula, 102
Silurus, 488
Sinus, longitudinal venous, of Limulus, 176, 312, 451
Sin”s, rhomboidal of bird, 46
Skeleton, Ammocœtes, 126, 296, 335
Skel”ton, Amm”cœtes, branchial, 126, 126
Skel”ton, Amm”cœtes, basi-cranial, 132
Skel”ton, Amm”cœtes, muco-cartilaginous, 291, 296, 330, 331
Skel”ton, aponeurotic, 414
Skel”ton, Cephalaspis, 414, 415
Skel”ton, evidence of the, 119
Skel”ton, Limulus, cartilaginous, 126, 136
Skel”ton, Lim”lus, mesosomatic, 137
Skel”ton, Lim”lus, prosomatic, 142
Skel”ton, Petromyzon, 125
Skel”ton, Vertebrate, commencement of bony, 120, 121
Skin, digestive power of cells of, in Ammocœtes, 58, 442
Si”n, of Ammocœtes, 346
Si”n, nerves of, 448
Skull of dogfish, 123
Skl”l of pig-embryo, 121
Slimonia, 27, 56, 170, 235, 238, 249, 276, 303
Solenocytes, 395, 477
Solpugidæ, 109
Sphæroma serratum, brain, 62, 90, 101, 225
Spiders, eyes, 75
Spi”ers, stomach, 109
Spina bifida, 50
Spinal cord, difference between brain and, 45
Spi”al cr”d, region of, 385
Spi”al cr”d, termination in bird-embryo, 51
Spondylus, retina of, 114
Squilla, eyes, 100
Sqi”lla, glands, 422
Stomach, cephalic, 4, 43, 102, 244
Stylonurus Lagani, 27, 235, 239, 249
Substantia gelatinosa Rolandi, 44
Suprarenal body, 423
Surfaces, dorsal and ventral, 11
Surf”ces, reversal of, 15, 29, 36, 87, 175, 352, 433, 484
Synapse, 72
Syncytium, 464, 471, 479
Tail of lizards, 50
Tapetum, 69
Teleosteans, 23, 345, 420, 424
Tendon-organs, 470
Tentacles of Ammocœtes, 246, 289, 303
Tergo-coxal muscles, 247
Test, biological, of relationship of animals, 492
Thalainencephalon, 48
Thelodus, 344
Thelyphonus, 231
Thely”honus, brain, 53, 54, 56, 224
Thely”honus, br”in, caudal, 450
Thely”honus, cœcal diverticula, 109
Thely”honus, entosternite, 143
Thely”honus, genital organs, 206
Thely”honus, lyriform organs, 368
Thely”honus, olfactory passage, 226, 306
Thely”honus, operculum, 189, 190, 206, 207
Theory, gastræa, 444, 461
Theories of the origin of vertebrates, 9, 411, 433, 457
Thionin reaction, 131, 139, 213, 330, 336
Throat, formation of, 179
Thyestes, 30, 31, 275, 326, 328, 329, 339, 340, 341
Thymus, 425, 430
Thyroid gland of Ammocœtes, 61, 127, 192, 194, 196, 429, 459
Thyr”id gl”nd evidence of the, 185
Thyr”id gl”nd function of, in Ammocœtes, 213
Tissues, connective, 471, 474, 481
Tiss”es, evolution of, 19
Tiss”es, notochordal, 435
Tiss”es, two groups of, 463
Tongue of Ammocœtes, 246, 303
Tonsils, 427, 430
Torpedo, 262, 392, 470
Trabeculæ, 121, 132, 133, 145, 277, 295, 377
Transformation of the Lamprey, 18, 35, 59, 61, 125, 168, 193, 199, 200, 220, 227, 228, 287, 291, 304, 307, 309, 331, 336, 347, 349, 389, 445
Tremataspis, 32, 75, 275, 326, 351, 352
Trilobites, 24, 25, 26, 437
Trilo”ites, appendages, 351, 437
Trilo”ites, diagram of section through a trilobite-like animal, 413
Trilo”ites, dominance of, 26
Trilo”ites, excretory organs, 396
Trilo”ites, eyes, 74, 88
Trilo”ites, glabellum, 339
Trilo”ites, relations of, 249, 283
Trilo”ites, respiratory apparatus, 170
Trilo”ites, ventral surface, 437
Tube of central nervous system, 37, 38, 42, 102, 211, 433, 455, 457
Tu”e from IVth ventricle to surface of brain in Ammocœtes, 209
Tu”e Fallopian, 431
Tu”e hypophysial, 229, 244, 317, 440
Tu”e meeting of four tubes in vertebrate, 318, 440
Tu”e notochord originally a, 436, 440
Tu”e olfactory, of Ammocœtes, 219, 225, 317, 440
Tu”e unsegmented, in segmented animal, 439
Tunicata, 16
Tuni”ata, budding of, 441
Tuni”ata, degeneration, 12, 17, 19, 60
Tuni”ata, endostyle, 198, 212
Tuni”ata, hypophysis, 425
Tuni”ata, notochord, 438
Tuni”ata, position of, 494
Unit, appendage, in non-branchial segments, 185
Ui”t, branchial, 161, 165, 168, 185
Ureters, nerves of, 448
Uterus of Scorpion group, 189, 202, 203, 204, 205, 214
Utr”us vertebrate, nerves of, 448
Valve, ileo-colic, 449
Val”e, of Vieussens, 48
Variation in dominant races, 21, 88
Vari”tion meristic, in spinal nerves, 154, 387
Veins, forming vertebrate heart, 180
Velum, 228, 289, 298, 302
Vertebrates, alimentary canal, innervation of, 446
Verte”rates, atrial cavity, 410
Verte”rates, auditory apparatus and lateral-line system, 356
Verte”rates, body-cavity, 401, 430
Verte”rates, brains, 40
Verte”rates, branchial organs, 151
Verte”rates, cœlomic cavities in head region, 251, 266
Verte”rates, cranium, evolution of, 342
Verte”rates, egg of, 483
Verte”rates, evolution of, 11
Verte”rates, excretory organs, 389, 391, 408
Verte”rates, glands, ductless, 418
Verte”rates, gla”ds, internal secretion of, 215
Verte”rates, heart, 175, 179, 180
Verte”rates, muscles, evidence of segmentation of eye, 248
Verte”rates, mus”les, oblique, 278
Verte”rates, mus”les, origin of somatic trunk, 406
Verte”rates, nervous system, central, 13
Verte”rates, nerves, segmental, 152
Verte”rates, notochord and gut, 434
Verte”rates, organs of, 10
Verte”rates, origin of, 9, 411, 433, 457
Verte”rates, segments, prosomatic, 257
Verte”rates, skeleton, commencement of bony, 120, 458
Verte”rates, spinal cord and medulla oblongata, 44
Verte”rates, spinal region, 385
Verte”rates, thyroid, connection between generative organs and, 215
Verte”rates, tubes, meeting of four, 318, 440
Vesicles, cerebral, formation of, 48, 458
Vitellophags, 471, 483
Volvox, 479
Wolffian body, 390
Xiphosura, 24, 26, 249
Yolk, 482
The End
Notes
1 N.B.—In addition to the nerves mentioned, C. Bell included, in his respiratory system of nerves, the fourth nerve or trochlearis, the phrenic and the external respiratory of Bell.
2 “The Origin of Vertebrates, deduced from the Study of Ammocœtes.” Part X., “The Origin of the Auditory Organ: the Meaning of the VIIIth Cranial Nerve.” Journ. Anat. and Physiol., vol. 36, 1902.