GENERATION OF ANIMAI^, I. xxiii. 



female are separate ; one animal is male and another 

 female, though they are identical in species, just as 

 men and women are both human beings, and stallion 

 and mare are both horses. In plants, however, these 

 faculties are mingled together ; the female is not 

 separate from the male ; and that is why they gener- 

 ate out of themselves, and produce not semen but a 

 fetation — what we call their '" seeds." Empedocles 

 puts this well in his poem, when he says " : 



So the great trees lay eggs ; the olives first . . ., 



because just as the egg is a fetation from part of 

 which ^ the creature is formed while the remainder 

 is nourishment, so from part of the seed is formed the 

 growing plant, while the remainder is nourishment 

 for the shoot and the first root. And in a sort of way 

 the same happens even in those animals where male 

 and female are separate ; for when they have need 

 to generate they cease to be separate and are united 

 as they are in plants : their nature desires that they 

 should become one. And this is plain to see when 

 they are uniting and copulating [that one animal is 

 produced out of the two of them]. 



The natural practice of those animals which emit 

 no semen is to remain united for a long time, until 

 <the male) has " set "the fetation : those Insects 

 wliich copulate are an example of this. Other 

 animals, however, remain united until the male has 

 introduced from those " parts " '^ of himself which he 

 inserts one which ^\-ill " set " the fetation but will 

 take a longer time to do so : the blooded animals 

 illustrate this. The former sort remain in copulation 



" See T33 a 29. 



* The use of " part " here to refer to semen is a good 

 illustration of the meaning of this term in Aristotle. 



123 



