No. 496] ASPECTS OF THE SPECIES QUESTION 279 



from their corresponding pigmented forms in no other 

 character but that of pigmentation. Whether Mendelities 

 may in any case be the initial modification leading to new 

 elementary species is not known, but I believe that we 

 are not yet warranted in so considering it. But elemen- 

 tary species and Mendelities are certainly natural entities 

 and must be used as the physiological units of form. 



Me. J. A. Harbis: It seems to me that while the sys- 

 tematists are receiving the congratulations of morphol- 

 ogists and ecologists, it will be well for us to remember 

 that he "that is without sin" among us "should cast 

 the first stone." I think in the present state of biology, 

 the morphologist and physiologist and ecologist have 

 some points to learn from the systematist, and that the 

 morphologist, physiologist and ecologist are to some ex- 

 tent responsible for our present inadequate knowledge of 

 species. 



The taxonomist has worked out a very careful scheme 

 of recording his observations; lie feels himself bound, in 

 preparing a monograph, to cite all descriptions. It is 

 perfectly easy to take a well-prepared monograph and to 

 follow out the earlier literature of any form. If, on the 

 other hand, one turns to morphological and physiological 

 writing, he will find it is a difficult task to locate the work 

 which others have done on the same species. It seems 

 to me that if the taxonomist is expected to make use of 

 experimental and ecological data in his limitation of 

 species, he should be given the data, by those who are 

 doing such work, in a form in which he can use them. 

 Take, for instance, our ecological papers. An ecologist 

 works on a certain region and refers to a number of 

 species definitely, and to a larger number of species in- 

 definitely, grouping them as glasses, sedges, asters, etc. 

 How is the taxonomist to utilize such data. The work 

 of the ecologist should be specific and comparative. He 

 should be explicit in his statements concerning the form 

 and life con. lit ions of a species in his own region, and 

 he should refer to the literature in such a detailed fashion 



