GENERATION OF ANIMALS, IV. iv. 



sizes corresponds to these differences. At the same 

 time, this does not hold good of all of them, because 

 the reason for their producing few or many offspring 

 is the size, great or small, of their bodies, not the 

 fact that that particular kind of animal is cloven- or 

 solid-hoofed or is fissipede. Here is a proof of this. 

 The elephant is the biggest of the animals, but it 

 is fissipede ; the camel, which is the next biggest, is 

 cloven-hoofed. And it is not only among the animals 

 that walk but also among those that fly and swim 

 that the big ones produce few offspring and the 

 small ones produce many ; and the cause is the 

 same. Similarly, too, it is not the biggest plants 

 that bear the most fruit. 



We have stated why the nature of some animals is 

 to produce many offspring, that of others to produce 

 few, that of others to produce one only. So far as the 

 puzzle which has now been mentioned is concerned, 

 one might rather be justifiably surprised in the case 

 of those animals Avhich produce many offspring, in 

 view of the fact that animals of this sort, as we see, 

 often conceive as the result of one act of copulation. 

 Now it may be that the semen of the male contributes 

 to the material <in the female) by becoming part of 

 the fetation and by mixing with the semen of the 

 female ; or it may be that it does not act in this way, 

 but, as we hold, acts by concentrating and fashioning" 

 the material in the female, i.e., the seminal residue, 

 just as fig-juice '' acts upon the fluid portion of the 

 milk ; but whichever of these views is right, what on 

 earth is the cause why the semen does not turn out 

 one single animal of a fair size, just as the fig-juice 

 acts in our example, (but that instead several ofF- 



» Cf. 767 b 17, 772 b 32. " See 737 a 15. 



433 



