ANIMAL LIFE GENERATION. 



Crustaceans). But we shall pass now to the 

 latter. 



2. Double Generation of Animal-life. 

 From the foregoing account we may observe 

 a striving of the animal toward a complete 

 dual sexuality, in which the separative ten- 

 dency of Nature would seem to culminate. 

 The difference of sexes in the higher animals 

 and especially in man shows the physical 

 world evolved to its last chasm, which, how- 

 ever, Is to be bridged by the generative deed. 

 It is no wonder, then, that the biology of to- 

 day has brought forward with so much indus- 

 trious research and experiment the problem 

 of Double Generation (getting now techni- 

 cally to be named amphigony), and has traced 

 it into the primal genetic cells of male and 

 female. Generation has thus become cellular, 

 in accord with the dominant biological task 

 of the time. The study of the behavior of 

 the sexual cells (spermatozoon and ovum) is 

 pursued in great detail with a singular fas- 

 cination as if the scientist himself expected 

 the next moment to witness his own genesis. 

 Of course this moment has not yet arrived, 

 and probably will not under the microscope; 

 but in the meantime we have learned many 

 other things. In this connection we may cite 

 an authoritative formula of Professor Hert- 

 wig of Munich: " Sexual reproduction is a re- 



