302 ON GENERATION. 



that it should be imbued with the animal principle. The egg, 

 consequently, is formed by the hen, but it is made prolific by 

 the cock. 



Aristotle adds in the same place : " There is a distinction 

 of sexes through the whole class of birds. And therefore it 

 happens that the hen perfects her egg, not yet influenced by 

 the intercourse of the male, in so far as it is a plant ; but as 

 it is not a plant, there she does not perfect it : nor does any- 

 thing come of it which engenders. For neither has it arisen 

 simply, like the seed of a plant, nor like an animal conception, 

 by intercourse/' He is here speaking of the wind egg; by and 

 by he adds : " But those eggs that are conceived through in- 

 tercourse are already characterized in a portion of the albumen : 

 such eggs become fruitful through the male which first copu- 

 lated, for they are then supplied with both principles." 



By this he seems to confess that the female is also effective 

 in the work of generation, or is possessed of the faculty of en- 

 gendering; because in every female there inheres a vegetative 

 soul, whose faculty it is to engender. And, therefore, when 

 he is speaking of the differences between the male and female, 

 he still acknowledges both as generative ; for he says : " We 

 call that animal male which engenders in another, female that 

 which engenders in itself." From his own showing, therefore, 

 both engender; and as there is a vegetative soul inherent in 

 both, so is there also its faculty of generation. But how they 

 differ has already been shown in the History of the Egg : the 

 hen generates of herself without the concurrence of the cock, 

 as a plant out of itself produces fruit ; but it is a wind egg 

 that is thus produced : it is not made fruitful without the con- 

 currence of the cock either preceding or succeeding. The female 

 generates, then, but it is only up to a certain mark, and the 

 concurrence of the male is requisite that this faculty of engen- 

 dering be made complete, that she may not only lay an egg, 

 but such an egg as will, under favorable circumstances, produce 

 a pullet. The male appears to be ordained by nature to supply 

 this deficiency in the generative powers of the female, as will 

 be clearly shown by and by, and that that which the female of 

 herself cannot accomplish, viz. the production of a fruitful 

 egg, may be supplied and made good by the act of the male, 

 who imparts this virtue to the fowl or the egg. 



