GENERATION OF ANIMALS, I. ii. 



physical parts. They differ in their logos, because 

 the male is that which has the power to generate in 

 another (as was stated above), while the female is 

 that which can generate in itself, i.e., it is that out 

 of which the generated offspring, which is present in 

 the generator," comes into being. Very well, then : 

 they are distinguished in respect of their faculty, and 

 this entails a certain function. Now for the exercise 

 of every function instruments are needed, and the 

 instruments for physical faculties are the parts of the 

 body. Hence it is necessary that, for the purpose of 

 copulation and procreation, certain parts should 

 exist, parts that are different from each other, in 

 respect of which the male will differ from the female ; 

 for although male and female are indeed used as 

 epithets of the whole of the animal, it is not male or 

 female in respect of the whole of itself, but only in 

 respect of a particular faculty and a particular part * 

 — ^just as it is " seeing " and " walking " in respect 

 of certain parts — and this part is one which is evident 

 to the senses. Now in the female this special part is 

 what is called the uterus, and in the male the regions 

 about the testes and the penis, so far as all the 

 blooded animals are concerned : some of them have 

 actual testes, some testicular passages. There are 

 also differences between male and female in those of 

 the bloodless creatures which have this opposition 

 of the sexes. In the blooded animals the parts which 

 serve for copulation differ in their shapes. We must 

 note, however,'^ that when a small principle '^ changes, 

 usually many of the things which depend upon it 



the statement just made (716 a 37 ff.). And cf. the passage 

 H.A. 583 b 31 If. Cf. also 764 b ;28, 766 a 24 ff. 

 '' See Introd. § 11. 



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