No. 596] SHORTER ARTICLES AND DISCUSSION 499 



divergent standpoints which bear upon the question are to be 

 welcomed. It is only through an analysis of the opinions thus 

 advanced that there will develop a perspective which will eventu- 

 ally permit the solution of the problem. 



It is in this connection that the conclusions of Professor Coulter 

 as set forth in "The Evolution of Sex in Plants" 1 are of interest, 

 representing as they do the views of one whose attainments in 

 biology have by no means been confined to the field of plant mor- 

 phology. Presented in a clear and interesting manner so fa r as t he 

 facts are concerned, the volume furnishes a valuable resume of 

 the subject from the botanical standpoint. It is evident, how- 

 ever, that a certain narrowness must exist in such a presentation, 

 for a problem of this nature demands that plant biology and ani- 

 mal biology supplement one another from the experimental as 

 well as from the morphological and cytological side. Gameto- 

 genesis had its beginning not, as Coulter suggests, among organ- 

 isms far above the most primitive plants, but among unicellular 

 flagellate forms whose representatives partake of the nature of 

 both plants and animals and from which have arisen the various 

 groups of plants in general. Sexuality, once having arisen, may 

 have been partially or even wholly suppressed in various plant 

 groups, but its subsequent reappearance by no means makes it 

 necessary to affirm its polyphyletic origin. Our present knowl- 

 edge of Mendelian behavior is of interest in connection with such 



It will be well to examine some of the more definite conclusions 

 which Coulter has presented. Few of these are original, never- 

 theless they are of decided value since they are in most cases sup- 

 ported 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 Chamberlain ('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 



