T. M. SONNEBORN 201 



a division of opinion on the most desirable usage of the techni- 

 cal term species. Until recently it has been used as a universally 

 applicable designation for pigeon-holing all organisms. Propo- 

 nents of the gene pool species concept have used the term in a 

 second sense which is inapplicable in principle to a large pro- 

 portion of all organisms and which can strictly be extended to 

 but an infinitesimal fraction of the eligible organisms because of 

 the great labor involved in applying it. The last difficulty is 

 minimized on the assumption that taxonomists have probably 

 already defined most species of outbreeders in such a way that, if 

 breeding studies were made, the taxonomists' species and the 

 biological species would be found to be identical. However, in 

 the absence of breeding studies, this remains only a more or less 

 reasonable conclusion. In any case, the gene pool species is more 

 restricted in applicability than the species of routine taxonomy. 

 Many taxonomists are unwilling to abandon the universal use of 

 the term for a limited use, and I agree with them. 



The alternatives seem clear. (1) Accept the double standard 

 of applying the biological species concept whenever information 

 justifies it and using routine taxonomic procedure in all other 

 cases, i.e., in the great majority. (2) Restrict the term species to 

 the limited group and find a new term for the majority. (3) Con- 

 tinue to use the term species in its universal pigeon-hole sense 

 and find a new term for the limited number of cases in which 

 common gene pools are known or will be discovered. I reject the 

 first alternative on the ground that a technical term should have 

 a single usage, and the second alternative on the grounds of pri- 

 ority and generality. Accepting, therefore, the third alternative, 

 I propose the term "syngen" for the potentially common gene 

 pool, for organisms capable of "generating together." I recom- 

 mend that it or a better term, if one can be found, should be 

 adopted. I am therefore prepared to abandon the use of the term 

 variety in P. aurelia in favor of syngen or whatever other new 

 term meets with the approval of the experts. But I am not will- 

 ing to abandon the term variety in favor of species, for the 

 reasons just given. 



