No. 501] 



THE SPECIES QUESTION 



ry.)5 



large extent the working basis of zoologists, it is evident 

 that they must necessarily fail to meet the needs of 

 botanists, where the minor differentiations are of such a 

 different character, and where so many and such diverse 

 conditions affect differentiation within groups formerly 

 recognized as species. Botanical nomenclature evidently 

 must remain a makeshift, satisfactory to no one, until the 

 ecological, physiological and experimental botanists have 

 come to a better understanding of the causes and rela- 

 tions of morphological and physiological differences 

 among closely related forms. 



The introduction of trinomial nomenclature into zo- 

 ology, while satisfactory for the designation of inter- 

 grading geographic forms, left still unsettled the old ques- 

 tion of how far it is profitable to recognize in nomen- 

 clature the minor morphologic differentiations. In the 

 cases of mammals and birds it was found necessary to 

 reduce many so-called species to subspecies, and also to 

 add, as material increased, many new forms under tri- 

 nomial designations. These were, of course, intergra- 

 ding forms, and hence arose the serious question of where 

 to stop bestowing names upon slight morphologic varia- 

 tions, restricted to limited and not very clearly defiued 

 physiographic areas. As no hard and fast rule can be 

 formulated, the treatment of such cases becomes largely 

 a matter of temperament, experience and good judgment, 

 in other words, the fitness of the taxonomer for his work. 

 As is well known, the American Ornithologists Union has 

 a permanent committee on the nomenclature and classi- 

 fication of North Amrican birds, whose function it is to 

 consider all proposed changes in nomenclature and all 

 proposed additions to the list of North American birds. 

 This committee, consisting of seven members, is reap- 

 pointed annually, and is subject to change in personnel. 

 Its reports are published from time to time in the form 

 of supplements to the A. 0. Check-List of North American 

 Birds, in which are given not only the accepted changes 

 of nomenclature and the additions to the list, but also 



