TllK NORTIIKKN (iRAY SQITRRKL. 



465 



Remarks. — One of the chief points of interest in connection with 

 this subspecies is the status of the dimorphic black phase. Where 

 the two forms occur, the black phase is always considered a distinct 

 species in the popular mind. The early American naturalists held 

 the same view, but Baird correctly placed the two color varieties 

 in the same species in his account of the mammals of North Amer- 

 ica, published as a volume of the Pacific Railroad reports in 1857. 



Almost thirty years later Merriam described a subspecies from 

 Elk River, IMinnesota, as Sciurus caroliuensis hypophaeus, the prin- 

 cipal characters being a dusky belly associated with the typical gray 

 coat of /S'. c. leucotis. While collecting along the Kankakee in Por- 

 ter County in 1905, the writer obtained a series of squirrel skins 

 which show gradations from the light grizzled back and white belly 

 of leucotis to the grizzled back and dark belly of hypophaeus, and 

 the almost complete black of the dark phase. Some of the speci- 

 mens have the ordinary gray back and at the other extreme the 

 squirrels appear to be entirely black unless closely examined, when 

 paler rings can be distinguished on some of the hairs. 



These and similar facts obtained by other collectors clearly indi- 

 cate that both the dark bellied and black varieties are forms which 

 may be produced by the common gray squirrel at any time or place 

 for causes as yet wholly unknown. Since they probably do not 

 breed true they cannot be considered as true species or subspecies. 



It is of interest to know that the black phase was formerly more 

 abundant in some parts of southern Indiana than they now are. 

 Dr. Ilaymond wrote in 1869 : "The black squirrels were common — 

 forming about one-third of the total number of squirrels in south- 

 eastern Indiana at the period of its first settlement. Now they have 

 completely disappeared. ' ' 



At New Harmony, however, Wied states that Lesueur saw but 

 one black squirrel in many years. The writer has not seen or heard 

 of a black squirrel in the southern part of the State in recent years. 

 In other states, also, it has been found that the black squirrels are 

 the first to disappear. This is no doubt due, in part, to the fact that 

 they are more conspicuous and are therefor killed off the more 

 quickly. It is possible, also, that they are, in a way, abnormal and 

 lack the vitality necessary to continue their kind under adverse 

 circumstances. In southern Porter and northern Jasper counties in 

 1905 the black or partially black s(|uirrels were nearly as numerous 

 as the gray. 



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