3. The seal is amphibious, for it does not inhale water, but breathes and sleeps. It produces its young on land, but near the shore, in the manner of animals with feet; but it lives the greater part of its time, and obtains its food in the sea, wherefore it is to be considered among aquatic animals. It is properly viviparous, and produces a living creature, and a chorion, and it brings forth the other membranes like a sheep. It produces one or two, never more than three young ones. It has also mammæ, so that it suckles its young like quadrupeds. It produces its young like the human subject, at all seasons of the year, but especially with the earliest goats.
4. When the young are twelve days old, it leads them to the water several times in the day, in order to habituate them by degrees. It drags its hinder parts along, and does not walk, for it cannot erect itself upon its feet, but it contracts and draws itself together. It is fleshy and soft, and its bones are cartilaginous. It is difficult to kill the seal by violence, unless it is struck upon the temple, for its body is fleshy. It has a voice like an ox. The pudendum of the female is like that of the batis, in all other animals of the class the pudendum resembles that of the human female. This is the manner of the development and nature of the young of aquatic animals which are either internally or externally viviparous.
1. The oviparous fish have a divided uterus placed on the lower part of the body, as I observed before. All that have scales are viviparous, as the labrax, cestreus, cephalus, etelis,[204] and those called white fish, and all smooth fish except the eel. Their ova resemble sand. This appearance is owing to their uterus being quite full of ova, so that small fish appear to have only two ova; for the small size and thinness of the uterus renders it invisible in these creatures. I have before treated of the sexual intercourse of fish. The sexes are distinct in almost all fish, though there is some doubt about the erythrinus[205] and the channa, for all these are found to be pregnant.
2. Ova are found in those fish which have sexual intercourse, though they possess them without intercourse. This is observable in some kinds of river fish; for the phoxini[206] appear to be pregnant as soon as they are born, and when they are quite small. They emit the ova in a stream; and, as I observed before, the males devour great numbers of them, and others perish in the water. Those are preserved which they deposit in their appropriate situations. For, if all were preserved, the numbers that would be found would be immense. Not all those that are preserved are fertile, but only those on which the seminal fluid of the male has been sprinkled. When the female produces her ova, the male follows, and scatters his semen upon them. Young fish are produced from those ova which are thus sprinkled. The remainder turn out as chance may direct.