B. VI.] THE HISTOEY OF ANIMALS. 153 



them by degrees. It drags its hinder parts along, and does 

 not walk, for it cannot erect itself upon its feet, but it con- 

 tracts 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. 



CHAPTER XII. 



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, 1 

 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 2 and the channa, for all these are 

 found to be pregnant. 



2. Ova are found in those fish which have sexual inter- 

 course, though they possess them without intercourse. 

 This is observable in some kinds of river fish ; for the 

 phoxini 3 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 situa- 

 tions. For, if all were preserved, the numbers that would 

 be found would be immense. Not all those that are pre- 

 served 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. 



1 Perhaps the Sea-bream, Sparus. 2 Perhaps Perca marina. 



3 Cyprmus Phoxinus. 



