232 Heredity. 



organized animals permanently affixed to the same spot, 

 and haying their sexes separated, the male element is in- 

 variably brought to the female; and we can see the rea- 

 son, for the ova, even if detached before being fertilized 

 and not requiring subsequent nourishment and protec- 

 tion, would be, from their larger relative size, less easily 

 transported than the male element. Hence, plants and 

 many of the lower animals are in this respect analogous. 

 In the case of animals not affixed to the same spot, 

 but enclosed within a shell, with no power of protrud- 

 ing any part of their bodies, and in the case of animals 

 having little power of locomotion, the males must trust 

 the fertilizing element to the risk of at least a short transit 

 through the waters of the sea. It would, therefore, be 

 a great advantage to such animals, as their organization 

 became perfected, if the males, when ready to emit the 

 fertilizing element, were to acquire the habit of approach- 

 ing the female as closely as possible. The males of va- 

 rious lowly organized animals have thus aboriginally 

 acquired the same habit which would naturally be trans- 

 mitted to their more highly developed male descend- 

 ants; and in order that they should become efficient 

 seekers, they would have to be endowed with strong 

 passions. The acquirement of such passions would 

 naturally follow from the more eager males leaving a 

 larger number of offspring than the less eager." 



Need for a more Fundamental Explanation. 



This is all undoubtedly true, as far as it goes, but it 

 does not cover the whole ground. The sexual passion of 

 the male is undoubtedly stronger, as a rule, than that 

 of the female, and as the existence of the species de- 

 pends upon the strength of this passion, there will un- 

 doubtedly be a selection of the most eager males. 



