ARVICOLA 747 



1910. Arvicola scherman exitus Miller, Proc. Biol. Soe. Washington, xxiii, 

 p. 21, March 23, 1910 (St. Gallon, Switzerland). Type in British 

 Museum. 



1910. Arvicola scherman exitus Trouessart, Faune Mamm. d'Europe.p. x. 



1911. Arvicola scherman exilis Lydekker, Zool. Record, xlvii (1910), 



Mamm., p. 54 (Accidental renaming of exitus). 



Type locality. — St. Gallen, Switzerland. 



Geographical distribution. — Alps (not known from the Italian 

 side) at moderate altitudes, and immediately adjoining lowlands 

 of Switzerland and France ; eastward into Tirol ; northward 

 into the Vosges Mountains ; limits of range not known. 



Diagnosis. — Sole nearly smooth ; palmar and plantar tubercles 

 much reduced, occupying distinctly less than half area of region 

 in which they occur ; length of hind foot, 22 to 25 mm. ; condy- 

 lobasal length of fully adult skulls, 33 to 35 mm. ; colour of 

 upper parts a light yellowish brown, usually without much black 

 clouding ; tail buffy throughout or evidently bicolor (never 

 uniformly blackish) ; auditory bullae not highly inflated, their 

 surface often irregularly flattened ; anterior loop of re, short and 

 wide. Habits strictly terrestrial, mole-like. 



External characters. — Compared with Arvicola ampMbius this 

 animal shows the following peculiarities in external form. Upper 

 incisors more conspicuously protruding from mouth, and lower 

 teeth also much exposed, the lower lip apparently too short to 

 cover them. Front foot with anterior tubercles much more 

 reduced as compared with posterior pair, the three together 

 scarcely half as large as postero-external pad. (In A. amphibius 

 the three anterior tubercles together decidedly exceed bulk of 

 postero-external pad.) Hind foot showing only a slight tendency 

 to " feathering." Sole with posterior portion nearly smooth. 

 Plantar tubercles occupying decidedly less than half surface of 

 area in which they occur, their size noticeably less than corre- 

 sponding pads at base of claws ; that at base of first digit 

 scarcely larger than a dust shot ; that at base of fifth toe about 

 three times as large, and sub-equal to the two other anterior 

 pads ; postero-internal tubercle larger and more elongate than 

 any of the others, but less noticeably so than in A. amphibius. 

 An exceedingly rudimentary sixth tubercle sometimes present. 

 Tail with annulations narrower than in A. amphibius, about 20 

 to the centimeter at middle. 



Colour. — Upper parts varying from a light broccoli-brown to 

 ochraceous-buff, the face, crown and median dorsal area faintly 

 darkened by blackish hair-tips, these usually most noticeable in 

 lumbar region ; sides in brightest specimens clear ochraceous- 

 buff, in others more nearly a greyish cream-buff; underparts a 

 paler, less slaty grey than in M. scherman scherman, the throat 

 nearly the grey No. 9 of Ridgway ; chest and belly washed with 

 cream-buff; feet ecru-drab, sometimes with a buffy tinge ; tail 



