1918.] Recently published Oniifhological Works. 729 



exaggerated their importance, and true perspective of values 

 is often completely lostj so that, with vision narrowed to 

 seek only dift'ereuces, nothing can be seen except a variation 

 to be named/' 



Briefly Dr. Dwight endeavours to show that instead of 

 accepting intergradation as a guide by which to separate 

 species from subspecies, it should be recognized that species 

 should be characterized by qualitative and subspecies by 

 quantitative characters. 



In illustration of his views Dr. Dwight takes the genus 

 Junco,an American group of the Fringillidse, whose breeding 

 range is confined to the Hudsonian and Canadian faunal 

 zones corresponding to the coniferous forests of the north 

 and the higlier elevations along the mountain ranges reaching 

 as far south as the volcanic peaks of Costa Kica. These 

 birds are exceedingly comuion at lower elevations during 

 the winter, but Dr. Dwight's studies have been almost 

 entirely confined to birds obtained during the breeding- 

 season. By a careful consideration of the geographical 

 distribution of the chief colour-characteristics of each group, 

 he arrives at his conclusions as to the taxonomy of the 

 genus^ recognizing nine distinct species with a number of 

 subspecies. 



A certain number of individual birds which do not fit 

 exactly into any of his species, but which combine the 

 characters of both in varying proportions, he regards as 

 hybrids; these of course are not comuion, and occur only 

 occasionally at the junction of the breeding ranges of the 

 contributing species. 



Though perhaps not accepting all Dr. Dwight's views in 

 their entirety, we are quite at one with him in confining 

 differential characters of subspecies to those which are 

 quantitative^ and regarding qualitative characters as of 

 specific value. In this way our nomenclature will give 

 us a far better view of relationship than by lumping 

 together large numbers of quite strongly differentiated 

 forms under one specific heading merely because they 



