° 1919 J Oberholser, Races of Quiscalus quiscula. 555 



Remarks. — This subspecies differs from both the other forms 

 of the species in its brownish bronze upper parts. Except for the 

 color of the head, it is very uniform, but this part might be con- 

 sidered to have three color phases: (1) purple, (2) blue, (3) green, 

 all of which are connected by intermediates. 



So far as the actual amount of difference in typical specimens 

 is concerned, it might well be called a species, but it so completely 

 intergrades at different points with Quiscalus quiscula ridgioayi, 

 that it seems best treated as a subspecies. At some other point 

 or points it abuts on either Quiscalus quiscula ridgioayi or Quiscalus 

 quiscula quiscula, and the lack of actual intergradation in such 

 places does not necessarily indicate that it is a distinct species, 

 because this condition is well known to exist in many races of other 

 species, between which, however, intergradation does occur at 

 other points. Nor can the fact that more or less typical specimens 

 of each of two intergrading forms occur in the same breeding 

 locality be considered as evidence of hybridism, since many sub- 

 species are known to intergrade in this way. In fact, a perfectly 

 gradual intergradation over a geographic area is rather the excep- 

 tion, since the individual variation in two forms often produces 

 considerable irregularity. This is frequently the case even when 

 the ranges do not actually meet, and such individual variation 

 must, in itself, of course, be considered intergradation. 



