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ARVICOLA RICHARDSONII . — A tj » . and Bach. 
Richardson’s Meadow-Mouse. 
PLATE CXXX V. — Natural Size. Fig. 1. 
A. fuscus nigro tinctus, subtus cineretis, caerulescente-canus, auriculis 
mediocribus vellere fere conditis, cauda capite paullulum longiore. 
CHARACTERS. 
Dull brown mixed with black, under parts bluish-gray ; ears, of moderate 
size, nearly hidden by the fur ; tail, a little longer than the head. 
SYNONYME. 
Arvicola Riparius? Ord. Bank Meadow-Mouse. Richardson, F. B. A., p. 120. 
DESCRIPTION. 
Head, rather large ; incisors, large, much exposed, and projecting beyond 
the nose — upper, flattened anteriorly, marked with scarcely perceptible 
perpendicular grooves, and with a somewhat irregular and rather oblique 
cutting edge — lower, twice as long as the upper, and narrower, slightly 
curved, and rounded anteriorly ; nose, thick and obtuse ; whiskers, few 
and rather short ; eyes, rather small ; ears, ovate, rounded at the tip, not 
easily distinguishable until the surrounding fur is blown or moved aside. 
Body, more slender behind than at the shoulders, the hind-legs not being 
so far apart as the fore-legs ; tail, rather short, tapering, and thinly covered 
with short hairs ; fore-legs, short ; feet, rather small, with four slender, 
well separated toes, and the rudiment of a thumb, which is armed with a 
minute nail ; claws, small, compressed, and pointed ; the third toe nearly 
equals the middle one, which is the longest. 
The hair of the toes projects over the claws but does not conceal them ; 
the toes of the hind-feet are longer than those of the fore-feet, and their 
claws are somewhat longer ; the inner one is the shortest, the second longer 
than the third, and the third longer than the fourth ; the first and fifth are 
considerably shorter than the others, and are placed farther back. 
The fur on the back is about eight lines long, but not so soft and fine as 
