GENERATION OF ANIMALS, I. v.-vi. 



and others inside. And as for those which have no M 

 testes, they lack this part, as we have said, because 

 such absence is not good, but necessary merely '^ ; 

 and also because it is necessarj' that their copula- 

 tion should be accomphshed quickly. Fishes and 

 serpents come under this class. Fishes copulate 

 bv placing themselves alongside each other and 

 quickly ejaculate.* Just as men and all such animals "^ 

 in order to emit the semen must of necessity hold 

 their breath, so fishes must refrain from taking in the 

 seawater,** and when they omit to do this they easily 

 come to grief. On this account they are bound to 

 avoid concocting * the semen during the act of copula- 

 tion (which is what the \i\iparous land-animals do) ; 

 instead, they have their semen ready concocted and 

 collected at the proper time, so that they do not con- 

 coct it while in contact \\-ith each other, but emit it 

 already concocted. For this reason they have no 

 testes, but passages which are straight and simple. 

 In the testes of quadrupeds there is a small portion 

 of a similar character : I refer to the latter portion of 

 that length of the passage which is doubled back.' 

 One portion of this length has blood in it and one has 

 not, and by the time the fluid enters this latter por- 

 tion and passes through it, it is already semen ; so 

 that when it arrives there, ejaculation quickly takes 

 place * in these animals too. In Fishes the whole of 

 the passage is of the same character as this latter 



' Cf.l\lh2b above, 



' The vas deferens; cf. above 717 a 33; and H.A. 

 510 a :?3 ff. 



' Cf. above, 718 a 1 ; Scot's Arabic original seems to 

 have been extremely cautious and to have given both possible 

 meanings of dn-oAuaij; for Scot has eius exitus est velox, et 

 cum exit sperma separantur mas etfemina. 



25 



