GENERATION OF ANIMALS, III. i. 



fluid and more bulky, whereas those of the high- 

 bred birds are leaner and more soUd," this being 

 the kind of body in which a thoroughbred and high- 

 spirited temper tends rather to make its appear- 

 ance ; also the thinness and weakness of their legs 

 contribute towards making these birds prone to 

 copulation and prolific — and this applies also to 

 human beings : the nourishment which was intended 

 for the legs is in such cases diverted to the seminal 

 residue : what Nature takes away from one place she 

 puts on at the other. The crook-taloned birds, on 

 the other hand, have strong feet, and their legs are 

 thick : this is due to their manner of life ; thus on 

 account of all these causes they do not copulate much 

 nor are they very prolific. The kestrel is the most 

 prolific of them, for this is practically the only one 

 of the crook-taloned birds which drinks, and the 

 fluid, both that which is innate and that which it gets 

 from without, is productive of semen when combined 

 with the heat which is present in it. Even this bird 

 does not lay many eggs ; four at the most. 



The cuckoo lays but few eggs although it is not a 

 crook-taloned bird, because it is cold by nature (as its 

 cowardice * clearly shows), whereas an animal that 

 is abundant in semen must be hot and fluid. That it 

 is cowardly is showTi by the fact that all other birds 

 chase it and that it lays its eggs in other birds' nests. 



Most birds of the pigeon kind usually lay a couple 

 of eggs. They are neither one-egg birds (there is no 

 one-egg bird beside the cuckoo, and this sometimes 

 lays two), nor do they lay a large number ; but they 



also 650 b 28 (o yap ^j3os Karou/ivxei-) and 667 a 17 fF., where 

 a large heart is said to produce cowardice because the heart 

 is so large that the heat is lost in so large a space. 



269 



