Natural History of the Mammalia of India and Ceylon

Section III Hystricomorpha — Porcupine-Like Rodents

This section contains six families, viz.:—

Octodontidæ	= 3 sub-families, 18 genera.
Hystricidæ	= 2 sub-families, 5 genera.
Chinchillidæ	= 5 genera, of which two are fossil.
Dasyproctidæ	= 2 genera.
Dionymidæ	= 1 genus.
Caviidæ	= 3 genera.

Of these we have to deal with but one, the second family, Hystricidæ, the rest belonging to Africa in part, but the majority to the American continent, chiefly South America.

I give the general characteristics of the section as laid down by Mr. Alston:—

“One premolar above and below (except in Ctenodactylus); grinding teeth rooted or rootless, not tuberculate; frontals with no distinct post-orbital processes (except in Chætomys); infra-orbital opening large, sub-triangular, or oval; zygomatic arch proportionately stout; molar not advancing far forward, (except in Ctenodactylinæ and Chinchillidæ) and not supported below by a continuation of the maxillary zygomatic process; incisive foramina small; foramina in the base of skull proportionally large; an inter-pterygoid fissure; mandible with its angular portion springing from the outer side of the bony covering of the lower incisor, triangular, usually pointed behind; coronoid process small, and condyle low; clavicles perfect or imperfect; fibula persistent as a distinct bone throughout life; upper lip rarely cleft; muffle clad with fine hairs; nostrils pointed above, sigmoid or linear; ears usually emarginate behind; tail hairy, sub-naked, or scaly.”—‘P. Z. S.,’ 1876, p. 90.

As I have said before, we have only to do with the Hystricidæ or Porcupines, but many of the others are familiar by name. Of the Octodontidæ the best known is the coypu of the Andes, one of the largest of the rodents, and the ground-rat or ground-pig of western and southern Africa. The chinchilla, which is the typical form of the third family, is known to all, especially ladies, from its delicate soft fur. The agouti of South America is the representative of the Dasyproctidæ. The family Dinomyidæ consists of one animal only, Dinomys Branickii; the only known example of which was obtained in Peru on the Montana de Vitoc. It was found walking about in a yard at daybreak, and showed so little fear of man that it suffered itself to be killed by the stroke of a sword. It is a pity no one was sensible enough to try and take it alive. As yet nothing is known of its habits. Of the last family, Caviidæ, the cavy and the capybara are well known to travellers in South America, and the common guinea pig is familiar to us all.