New to the United States. 3 



(o base of tail, and becoming indistinct on the head after passing 

 between the ears. Ears externally concolor with back, inter- 

 nally buff-yellow; muzzle grayish brown; whiskers mixed 

 brownish and whitish, the longest hairs reaching beyond 

 shoulders ; tail thinly haired, so that the annulation shows dis- 

 tinctly, sharply bicolor, dark brown, except ventrally and at tip. 



Among the specimens of Zapus insignis that I have examined 

 I find but little individual variation in color. That which occurs 

 seems to be due chiefly to season, spring specimens having the 

 sides brighter fulvous than those taken in the autumn and late 

 summer. The dorsal stripe is darker and more sharply defined 

 in some specimens than in others, the variation being caused by 

 the relative quantities of blackish and fulvous hairs. In speci- 

 mens with perfect tails the extent of the white tip varies from 

 30 mm. down to a mere trace; but the latter condition is rare, 

 occurring only twice in the series before me, most tails showing 

 from 10 mm. to 20 mm. of white. 



The four males taken at Elizabethtown, N. Y., in April are 

 brighter colored than the type and have apparently longer ears. 

 These discrepancies are probably due entirely to the different 

 condition of the specimens. Skins taken at Peterboro, N. Y., 

 late in August and early in September are nearly as dull as the 

 three from Restigouche, while the June specimen from North- 

 umberland county, N. B., less than one hundred miles from the 

 type locality, is fully as bright as any that I have seen. This 

 specimen (No. 1438) is alcoholic, but the comparison was made 

 a few days after its capture. The ear of No. 1438 is somewhat 

 longer than that of an alcoholic specimen (No. 2000) from Peter- 

 boro, while the ears of Mr. Batchelder's specimens from Keene, 

 N. Y., measure dry only a trifle more than the ears of the Resti- 

 gouche skins. 



On comparing thirty-eight skins of Zapus insignis with about 

 one hundred specimens of Z. hudsonius from various parts of 

 New Brunswick and the eastern United States, the paler, more 

 fulvous coloration of the former at once strikes the eye. The 

 ground color of the lateral stripe in hudsonius is more strongly 

 tinged with clay color and is much more plentifully interspersed 

 with black bristly hairs. There is no tendency in hudsonius to 

 form the clear yellow area on the sides of the head and fore neck 

 so conspicuous in Z. insignis. In the former, however, the clear 

 yellow line separating the lateral stripe from the white of the 



