﻿Dec, 1895.] 



BLAKINA BREVICAUDA. 



11 



Type Jocality. — West bank of Missouri Eiver, near Blair, Nebr. 

 (formerly Engineer Cantonment, 3 miles above month of Boyer River). 



Geograpliic distrihution. — Upper Austral and Transition zones, from 

 western Nebraska and Manitoba eastward to tlie Atlantic Coast, pene- 

 trating a sliort distance into lower edge of boreal. 



HaMtat. — Ckiefly deciduous woodlands and fields, where it lives in 

 shallow tunnels that are often marked on the surface by little ridges. 



General chamcters. — Size largest of the subgenus (total length about 

 125 mm.); skull largest and heaviest of the American Soricidw; pelage 

 glossy. 



Color. — Sooty-plumbeous above, becoming ashy-i^lumbeous below, 

 varying with the light; paler in summer; glossy in fresh j)elage. 



Cranial characters. — Skull large, massive, and angular (averaging 23 

 to 25 mm. in greatest length, and about 13 mm. in greatest breadth) ; 

 occipital plane relatively large, nearly flat, and slox)ing strongly for- 

 ward (not arched). The brain case j)resents the maximum of angularity 

 known in the group, and is highest at the lambdoid suture. The ramus 

 of the jaw is angular, being bent rather abruptly upward opposite 

 the last molar. The upiier lateral incisors contrasted with those of 

 carolinensis are relatively narrower at base and slope more strongly 

 forward; the first upper i^remolar (5th unicuspid) is usually visible 

 from the outside. 



Measurements. — Average of 8 specimens from near type locality: 

 Total length, 127 mm.; tail vertebrae, 26.5 mm.; hind foot, 16.5 mm. 

 Average of 31 specimens fi^om Lake George, 'New York: Total length, 

 122 mm. ; tail vertebrie, 26.5 mm, ; hind foot, 15 mm. Average of 6 speci- 

 mens from ]\farthas Vineyard, Massachusetts: Total length, 115 mm.; 

 tail vertebrie, 22 mm.; hind foot, 13.4 mm. 



General remarlcs.—BJarina hrevicauda presents considerable variation 

 in size and tint of color. The largest specimens are from western 

 Nebraska, and those from eastern Nebraska (type locality) are larger 

 than specimens from the Northern and Eastern States. From the type 

 locality as a center, decrease in size takes place to the north, east, 

 and south. Specimens from both sides of the Canadian boundary, be- 

 tween Manitoba and Lake Superior, are decidedly smaller than those 

 from Nebraska, Iowa, and southern Minnesota, but larger than 

 those from the Atlantic States. The smallest specimens I have seen 

 are from eastern Massachusetts, llirough the courtesy of Mr. Gerrit 

 S. Miller, jr., I have been able to examine a number of skulls in his 

 private collection from the following localities near the coast of that 

 State: West Dedham, Wareham, Provincetown, Seekonk, Marthas 

 Vineyard, and Nantucket. These skulls agree closely among them- 

 selves and average 22 mm. in greatest length (including incisors) and 

 12 mm. in breadth. Specimens from Nova Scotia, Ontario, New 

 Hampshire, and Maine are larger, agreeing with those from the Adi- 

 rondacks. The latter, however, are decidedly smaller than typical 



