Chap. 33 Gills and Scales
Some fishes have numerous gills, others again single2433 ones, others double; it is by means of these that they discharge the water that has entered the mouth. A sign of old age2434 is the hardness of the scales, which are not alike in all. There are two lakes2435 of Italy at the foot of the Alps, called Larius and Verbanus, in which there are to be seen every year, at the rising of the Vergiliæ,2436 fish remarkable for the number of their scales, and the exceeding sharpness2437 of them, strongly resembling hob-nails2438 in appearance; these fish, however, are only to be seen during that month,2439 and no longer.