PEDICECETES PHA.SIANELLUS VAR. COLUMBIANUS 409 



There is miicli less of the buff', tawny, or brownish-yellow variegation, 

 so conspicuous in the latter. The general colors might be called browu- 

 ish-blacii and white in the former, the markings disposed in a jtatteru 

 common to both varieties, yet the fulvous of var. columbianus assuming 

 a dark browu cast. In the northern bird the angular dark-markings 

 on the white ground of the under parts are almost black, and acutely 

 arrow-head shaped for the most part; in the southern, these markings 

 are much lighter brown, and, excepting generally the hinder ones, have 

 a more rounded outline. In the northern bird the throat is white, 

 speckled with blackish ; in the southern it is tawny, and nearly or quite 

 unmarked. Now these are the prominent characteristics, as they obtain 

 in the more strongly marked examples. But it must be remembered 

 that they are mixed and obscured in every degree in the complete and 

 gentle intergradation which obtains between the two varieties, ]>roving 

 them to be but a single species; Along the United States northern 

 boundary, and rather to the northward, specimens are more or less per- 

 fectly intermediate between the two extremes above noted. There is, 

 moreover, in both forms, such a difference between the breeding and 

 the autnmnal plumages (the latter being the lighter), as to further 

 prove the impossibility of specific distinctions being established. Birds 

 that I killed in June and July along the northern border of Dakota, 

 decidedly approached the dark northern form ; their offspring, shot in 

 the same locality the following September, when they were full grown, 

 very clearly pertained to the southern. They were all, indeed, much 

 lighter than the heaviest colored a»ctic birds ; but the old ones had the 

 white and speckled instead of buff throat, and so had the young ones 

 through the summer; they only assumed the buff throat, and thus dis- 

 tinctively showed their relationship with the southern form, after the 

 September moult. Speaking geographically, as well as zoologically, it 

 is impossible to assign limits to the two forms. All the United States 

 specimens I have seen, however, are unquestionably var. colmnhianus ; 

 and we may as well conventionally fix its limit along our present politi- 

 cal boundaiy, although the other variety only attains its special char- 

 acteristics in all their purity considerably further north. 



The northern line of distribution of var. cohimbianns being thus deter- 

 mined, we have to note its dispersion in other directions. Its eastern 

 limit offers interesting considerations of a different character; for in 

 this direction we find the bird to have been affected, not by climatic 

 influence modifying its physical characters, but by less obscure agencies 

 operating to gradually restrict its range. These agencies are directly 

 consequent ui)on the advance of civilization, which, very singularly, 

 pushes the Sharp-tailed Grouse continually westward, and at the same 

 time carries along with it the Pinnated Grouse. There is abundant 

 evidence that the Sharp-tailed once ranged much further east than it 

 does now ; and so rapidly is it being driven westward that a decided 

 change has been affected within the memory of those now living. How 

 far eastward it may have once ranged is uncertain. We have in the 

 earlier accounts some vague and evidently not reliable allusions to the 

 Sharp-tailed Grouse as an inhabitant of Virginia. This may or may not 

 have been the case, most probably it was an entire mistake ; and yet 

 there is no a priori reason against it. The Sharp-tailed is no more 

 exclusively a prairie-bird than the Pinnated, which we know once 

 ranged across the whole country, and lingers to this day in certain 

 isolated localities in the Middle States and even New England. Under 

 later and more authentic dates we find the Sharp-tailed Grouse men- 

 tioned by Audubon, in 1838, as " accidental in the northern parts of 



