HEREDITY AND VARIATION 213 



for a moment to consider how frequently the 

 characteristics of the male parent appear in 

 the offspring. When I was thinking over this 

 chapter yesterday I happened to see a mongrel 

 with whose parentage I was fully acquainted, 

 since she was the offspring of a pure-bred black 

 cocker spaniel of my own and I regret to say 

 an Irish terrier. The result is a red-haired 

 dog not very like either of her parents, but in 

 no way resembling her spaniel mother. This 

 and thousands of other cases prove if proof 

 were needed that the main purpose of the 

 spermatozoon is to introduce elements from 

 the other or male parent. The other effect is 

 very possibly there; but it is hardly the main 

 effect. To return to the quotation : 



" Loeb argues that the change in the surface 

 membrane is of a chemical character, and that 

 no doubt may be correct ; but even if we allow 

 him every scientific fact, or surmise, he is still, 

 as in the other cases with which we have dealt, 

 miles away from any real explanation. He is 

 still inside his chemico-physical explanation to 

 begin with; and, even within that, he still 

 leaves us anxious for the explanation of a 

 number of points for example, as to the 

 nature of the chemical process which accom- 

 panies, or is the cause of, segmentation. We 

 in no way press these questions ; for similar 



