590 Species According to the TJicory of Mutation. 



sa maniere de voir, line association de formes voisines."^ 

 On the other hand Jordan, as is well known, based his 

 conception of the smaller or elementary species as the 

 real species on the same fundamental proposition. The 

 wish to see in the s])ecies something real, has always 

 played a prominent part ; but the reality as it appeared 

 to the descriptive biologist has been very different from 

 that in the mind of the experimental investigator. 



It would certainlv 1)e desirable to aq:ree to call onlv 

 one of the two groups species ; it is only the question 

 which. The older view and the popular idea limit this 

 term to the larger groups, and give the name of sub- 

 species to the smaller ones.- But the term subspecies, 

 as it is now in use does not signify a unit, but a group 

 of units which is also compound and merely differs from 

 the species itself in being smaller (Part I, p. 60). The 

 modern tendency is to regard the smaller types as spe- 

 cies, and wherever the criterion is of an exi^erimental 

 kind, like that employed by Jordan, this view will ])re- 

 dominate. Its importance to descriptive biology has re- 

 centlv been demonstrated in a most clear and convincinsf 

 manner by Belli :^' and there seems every pros]~)ect of its 

 being recognized by the best systematists. 



It has been proposed to denote collective species by 

 a special name, and the word ''stirp" has been suggested. 

 This term has been applied in this sense by several svs- 

 tematists,"^ and Belli has adduced a long series of histor- 



' Alph. de Caxdoi.le. Archiv. dcs sc. dc la hlhJ. uuhcvscUc, Ge- 

 neva, Febr. 1878, Vol. LXI, p. 4. 



" hi what follows, I shall leave varieties, in the sense in which 

 this term has been used in the foregoing sections, out of account. 



'' S. Belli, toe. cit. 



"For instance, H. Leveille. Monographic du genre Oenothera, 

 1902, T. pp. '/2, 106, etc. 



