Chapter XVII.

1. Many sanguineous animals become torpid, as those which are furnished with scales, the serpent, lizard, gecko, and the river crocodile, during the four winter months in which they eat nothing. Other serpents conceal themselves in the earth, but the viper lies hidden among stones. Many fish also become torpid, especially the hippurus and coracinus during the winter; for these alone are never taken but at certain seasons, which never vary. Almost all the rest are taken at all seasons. The lamprey, orphus, and conger conceal themselves. The rock fish conceal themselves in pairs, as the cichla, cottyphus, and perca, the male with the female, in which way also they prepare for their young.

2. The tunny conceals itself during winter in deep places, and they become fattest at this season. The season of capturing them commences with the rising of Pleiades, and continues to the end of the setting of Arcturus. All the rest of their time they remain quiet in concealment. A few of these are taken during the period of their concealment, and so are some other hybernating creatures, if they are disturbed by the warmth of their abode or the unusual mildness of the season. For they come out a little from their holes to feed, and also when the moon is full. Most fish are better tasted during the period of concealment. The primades bury themselves in the mud. This is shown by their not being taken, or their seeming to have a great deal of mud on their backs and their fins pressed down.

3. In spring, however, they begin to move and come to the shore to copulate and deposit their ova. At this season they are captured full of ova, and then also they appear to be in season, but are not so good in autumn and winter. At the same season also the males appear to be full of melt. When their ova are small they are taken with difficulty; but as they grow larger many are taken when they are infested by the œstrus. Some fish bury themselves in sand, others in mud, with only their mouths above the surface. Fishes usually conceal themselves only in the winter. The malacostraca, the rock fishes, the batus, and selache only in the most severe weather. This is shown by the difficulty of capturing them in cold weather.

4. Some fish, as the glaucus, conceal themselves in summer time; for this fish hides itself for sixty days in the summer time. The onus and the chrysophrys hide themselves. The reason for supposing that the onus hides itself for a long while appears to be that it is captured at long intervals; and the influence of the stars upon them; and especially of the dog-star, appears to be the cause of their hiding themselves in summer time, for the sea is then disturbed. This is most conspicuous in the Bosphorus; for the mud is thrown up, and the fish are thus brought to the surface; and they say that, when the bottom is disturbed, more fish are often taken in the same cast the second than the first time; and after much rain animals make their appearance which before were either not seen at all or but seldom.