SWAETH — RED SQUIBREL OP SITKAN DISTRICT 93 



Diagnosis. — A red squirrel with the general characters of Sciurus hudsonicus. 

 Cranially, most nearly resembling Sciurus hudsonicus petulans; externally, more 

 nearly like S. h. vancouverensis. 



Comparisons. — Sciurus h. petulans, as compared with vancouverensis, is stated 

 by Osgood (N. Am. Fauna, No. 19, 1900, p. 27, pi. V, figs. 1, 2) to have the "nasals 

 longer and posteriorly more compressed than in vancouverensis; orbital arch with 

 a sharp indentation between lachrymal and postorbital process." These differ- 

 ences do not exist between petulans and picatus. There are individuals in the 

 latter series that show intergradation toward vancouverensis in shape of nasals 

 or in partial elimination of the orbital indentation described, but the series as 

 a whole is, cranially, not to be distinguished from petulans. 



As regards color, Sciurus h. picatus is dark as compared with petulans, but it 

 is distinctly brighter than vancouverensis. The differences are most apparent 

 in winter pelage ; in the summer coat the two forms are closely similar in general 

 appearance, differing only in certain minor details. In the winter coat vancou- 

 verensis is nearly uniform dark chestnut above, with the reddish dorsal stripe 

 poorly defined; the tail is reddish above, but decidedly grayish on the ventral 

 surface. In picatus the reddish color is generally brighter, there is a fairly well- 

 defined hazel dorsal stripe and the center of the tail below is reddish. The black 

 lateral stripe on the body is much more prominent. In all pelages picatus has 

 the tip of the tail much less extensively black than is the case with vancouver- 

 ensis. Sciurus h. picatus is slightly the larger of the two. For external measure- 

 ments of Sciurus h. picatus and S. h. vancouverensis see Swarth, Univ. Calif. Publ. 

 Zool., vol. 10, 1912, p. 88. 



Distribution. — The area inhabited includes parts of the Sitkan district, Alaska, 

 and extends for an undetermined distance southward. There are specimens at 

 hand from the following islands: Kupreanof, Kuiu, Mitkof,Wrangell, Zarembo, 

 Etolin, Revillagigedo, and Sergief . From mainland points : Taku River, Thomas 

 Bay, Stikine River, Bradfield Canal, Chickamin River. (For details of distri- 

 bution see Swarth, Univ. Calif. Publ. Zool., vol. 7, 1911, pp. 118, 153, map, fig. 1.) 



Remarks. — The material upon which the above comparisons are 

 made is as follows: Sciurus h. vancouverensis, 28 specimens from Van- 

 couver Island (Mus. Vert. Zool.). Sciurus h. picatus, 36 specimens 

 from the Alaskan localities previously indicated (32 in Mus. Vert. 

 Zool., 4 in the E. P. Walker collection). Sciurus h. petulans, 17 from 

 Glacier Bay (Mus. Vert. Zool.), 4 from Wells, Chilkat Valley (E. P. 

 Walker collection). 



The Glacier Bay specimens appear to be typical of petulans. The 

 four skins from Chilkat Valley are, in color, intermediate between 

 petulans and picatus; the skulls are not available. In his description 

 of petulans, Osgood (loc. cit.) treats vancouverensis as a distinct species, 

 a view that has since been disregarded (see Miller, List of North Amer- 

 ican Land Mammals, 1912, p. 321), and which my own material con- 

 troverts. The race picatus is in itself intermediate between petulans 



