448 Evolution and Adaptation 
accomplished by the normal method of fertilization that is 
here absent. This may mean no more than that as yet we 
have not found all the conditions necessary to supply the 
place of the spermatozoon. 
In our study of the phenomena of adaptation we have 
found that sometimes the adaptation is for the benefit of the 
individual and at other times for the benefit of the species. 
May it not be true also that the process of sexual reproduc- 
tion has more to do with a benefit conferred on the race 
rather than on the individual? In fact, Weismann has 
elaborated a view based on the conception that the process 
of sexual reproduction is beneficial to the race rather than to 
the individual. His idea, however, is not so much that the 
result is of direct benefit to a particular species, as it is ad- 
vantageous to the formation of new species from the original 
one. In a sense this amounts, perhaps, to nearly the same 
thing, but in another sense the idea involves a somewhat 
different point of view. 
According to his view “the deeper significance of conjuga- 
tion” and of sexual reproduction is concerned “with the 
mingling of the hereditary tendencies of two individuals.” 
In this way, through the different combinations that are 
formed, variations which he supposes are indispensable for the 
action of natural selection originate. The purpose of the 
sexual process is solely, according to Weismann, to supply 
the variations for natural selection. If it be asked how this 
process has been acquired for the purpose of supplying nat- 
ural selection with the material on which it can work, we find 
the following reply given by Weismann. “But if amphi- 
mixis [by which he means the union of sex-cells from different 
individuals] is not absolutely necessary, the rarity of purely 
parthenogenetic reproduction shows that it must have a wide- 
spread and deep significance. Its benefits are not to be 
sought in the single individual; for organisms can arise by 
agamic methods, without thereby suffering any loss of vital 
