LEE BARKER WALTON 127 



ing arisen, may have been partially or even wholly sup- 

 pressed in various plant groups, but its subsequent reap- 

 pearance by no means makes it necessary to affirm its 

 polyphyletic origin. Our present knowledge of Mendelian 

 behavior is of interest in connection with such a view. 



It will be well to examine some of the more definite 

 conclusions which Coulter has presented. Few of these 

 are original, nevertheless they are of decided value since 

 they are in most cases supported by unique observations 

 bearing directly upon the point of view. It is merely 

 unfortunate that the bibliographic references which would 

 illustrate the development of the ideas are entirely absent, 

 in consequence of which a false impression may be con- 

 veyed to many readers. 



Early in the volume it is stated that sex in the higher 

 animals has become the only method of reproduction. 

 Logically this view is not to be maintained, as has already 

 been pointed out by LeDantec ('03) as well as by Cham- 

 berlain ('05) evidently in ignorance of the conclusions 

 reached by the previous writer. More recently Janet ('12) 

 has considered the subject. If the criterion by which the 

 sporophyte is to be distinguished from the gametophyte 

 rests upon the Ix as compared with the x condition of the 

 chromosomes, we find that among animal organisms the 

 asexual phase has actually become the dominant method 

 of reproduction and the sexual phase is represented only by 

 the parasitic cells arising through the reduction division. 

 In accordance with this view one is prepared to accept the 

 spore mother cells of plants as homologues of the cells 

 preceding the reduction division in animals. In a sub- 

 sequent discussion Coulter states in accordance with the 

 view first advocated that the animal body produces gam- 

 etes and not spores. When reduction occurs at the time 

 of the first maturation division in animal organisms it is 

 quite clear that the cells thus produced may correspond 

 to spores which in the next division give rise to gametes. 

 It may even be asserted that they are megaspores or micro- 

 spores dependent on the sex represented. When chromo- 

 some reduction is moved forward to the second matura- 

 tion division, however, it is possible to agree with Coulter, 



