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ARVICOLA BOREALIS.— Rich. 
Northern Meadow-Mouse. 
PLATE CXXIX.— Male and. F emales. 
A. ungue pollicari robusto prmditus, auriculis vellere absconditis, cauda 
capitis fere longitudine, vellere longissima molli, dorso castaneo nigro 
mixto, ventre cano. 
CHAKACTEBS. 
Thumb nail , strong ; ears, concealed in the fur ; tail, about as long as the 
head ; fur, very long and fine j on the back, chesnut colour mixed with black ; 
on the belly, gray. 
SYNONYMES. • 
Mouse No. 15. Forster, Philos. Trans., vol. lxii. p. 380. 
Arvicola Borealis. Rich., Zool. Jour., No. 12, April, 1828, p. 51V. 
“ “ Northern Meadow-Mouse. F. B. A., p. 12V. 
Arvinnak. Dog-Rib Indians. 
DESCRIPTION. 
This species is a little less than Wilson’s Meadow-Mouse (Jl. Pennsylva- 
nica). It has the form and dentition of the other species of Arvicola:. 
Head, rather large ; forehead, convex ; nose, short, and a little pointed ; 
eyes, small ; ears, low, rounded, and concealed by the surrounding fur ; 
limbs, rather robust, clothed with short hairs, mixed on the toes and hind 
parts of the fore feet with longer hairs. Hind toes, more slender, and 
scarcely longer than the fore ones ; fore claws, small, much compressed, 
arched, and acute, with a narrow elliptical excavation underneath ; the 
hairs of the toes reach to the points of the nails, but cover them rather 
sparingly ; the claws of the hind feet resemble those of the fore feet, but 
are not so strong ; the thumb of the fore feet consists of a small squarish 
nail slightly convex on both sides, and having an obtuse point projecting 
from the middle of its extremity ; the tail is round, well clothed with short 
stiff hairs running to a point, which do not permit the scales to be visible. 
There are considerable variations in the length of the tail, it being in one 
specimen a third longer than in others. The fur on the body is long in 
proportion to the size of the animal. 
