GENERATION OF ANIMALS, III. v. 



A proof that these fishes as well as the others V 

 produce eggs is that even the viviparous fishes, such theories"* 

 as the Selachia, produce eggs internally at the first (i) Fish are 

 stage. Why is this a proof ? Because " it is plain that ous and do 

 the nhok of the tribe of fishes is oviparous. At the l^^^^^ 

 same time, no eggs of this sort reach perfection, — i.e., 

 eggs of species where both males and females exist, 

 and which are formed as the result of copulation '' — 

 unless the male sprinkles his genital fluid (milt) upon 

 them ; though there are some people who hold — ■ 

 incorrectly — that all fish are female apart from the 

 Selachia. Their \\e\v is that the females differ from 

 what are reputed to be males in the same way as 

 those species of plants in which one tree will bear 

 fruit and another \vill bear none (e.g., the olive and 

 oleaster, the fig and caprifig).*^ They say it is just 

 the same with fish, except in the case of the Selachia, 

 where they do not dispute the point. But as a matter 

 of fact there is no difference as regards their seminal 

 parts between males of the Selachian fishes and males 

 which belong to the oviparous group, and semen can 



doubt there were some who maintained that the eggs of 

 fishes, which Aristotle holds to be true, though " imperfect," 

 eggs, were on a par with the " eggs " out of which caterpillars 

 and the like developed : the latter, however, Aristotle holds 

 to be " larvae " and not true eggs (see 738 b 9 ff.) ; and 

 larvae, of course, are often found in connexion with creatures 

 in which (according to Aristotle) the sexes are not distinct and 

 are formed without copulation. Thus, the two points on 

 which Aristotle insists, (1) that fishes have sexes and copulate, 

 and (2) that they produce eggs, not larvae, are mutually- 

 corroborative. 



* The exception is the erythrlnus ; see 741 a 36, n. 



' See at)ove, 715 b :?5 : also H.A. 557 b 31. There seems 

 to be no similar phenomenon in the case of the olive, but it 

 was a common practice to call some trees male and others fe- 

 male : see Theophr. Hist, plant. 1. 8. 5, and cf. Soph. Tr. 1 196. 



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