Jan.. 191S] Status of Em pidouax Tniillii 87 



The geographic variation in this subspecies is not great. 

 Breeding birds from Maine and New Brunswick seem to be 

 absolutely indistinguishable from those taken at the same time 

 of year in Maryland and in Mackenzie, Canada. Furthermore, 

 birds that breed at Fort Keogh, Montana, appear to be prefectly 

 typical. Birds from North Dakota, South Dakota, Nebraska, 

 northeastern Colorado, and extreme western Montana are 

 intermediate, in that there is among them more individual 

 variation, rendering some individuals difficult to distinguish 

 from the bird of the far western United States. They are, 

 however, as a whole, decidedly nearer the eastern race. Like- 

 wise, breeding birds from Ohio, Indiana, Illinois, Arkansas, 

 Missouri, and Iowa, as well as from Michigan and Wisconsin, 

 must be referred to the New England race. This, therefore, 

 obliterates the zonal distinction between the breeding ranges 

 of the two forms of this species, which Mr. Brewster* has 

 delineated. 



One of the things brought out by the present study is the 

 great and very complicated individual color variation that 

 exists in both geographic races, which greatly increases the 

 difficulty of identifying individual specimens. The wing-bars 

 in the eastern bird are usually whitish, more or less tinged with 

 yellow or greenish, but occasionally these are decidedly brown- 

 ish, much resembling those of the western form of the species. 

 The lower parts are sometimes as yellowish below as in Empi- 

 douax I'irescens, but are usually more grayish or whitish. 

 Furthermore, the upper parts exhibit at least six more or less 

 well marked color phases, which, by individual variation, merge 

 imperceptibly into each other, so that there exists an infinite 

 variety of coloration. These phases, if such they may be called, 

 fall naturally into two series, separated in a general way by the 

 pattern of the upper surface. In one the color is almost 

 uniform from forehead to upper tail-coverts, and the type of 

 Muscicapa traillii Audubon is a bird of this kind; in the other 

 style the pileum and cervix are, in color, conspicuously different 

 from the back, being either more brownish or grayish and 

 forming a rather well defined cap. Birds of each one of these 

 styles exhibit three color phases: (1) dark greenish, which is 

 apparently the normal coloration, in which the upper parts are 



*Auk, XIT, Xo. 2, April, 189."), p. l.J9. 



