748 



RODENTIA 



whitish throughout or sprinkled witli blackish above, sometimes 

 rather distinctly bieolor. 



Skull and teeth. — The skull is slightly smaller than that of 

 Arvicola scherman scherman (condylobasal length in fully adult 

 specimens seldom if ever exceeding 35 mm.), and the fossorial 

 characteristics, particularly the sliallowness of the rostnnn as 



Fig. 154. 

 Arvicola scherman exitus. Nat. size. 



compared with brain-case, are carried to the extreme. Teeth as 

 in the typical form, but upper incisors even more strongly 

 projecting. 



Measurements. — ^External measurements of type (adult female) : 

 head and body, 138 ; tail, 64 ; hind foot, 24 ; ear, 13. Average 

 and extremes of eight adults from the type locality : head and 

 body, 146-6 (135-165); tail, 62-7 (56-70); hind foot, 23-7 

 (23-25). Adult male and female from Vitznau, Lucerne, 

 Switzerland: head and body, 131 and 133; tail, 67 and 61; 

 hind foot, 24 • 5 and 23 • 5 ; ear, 13 and 12. Average and extremes 

 of six adults from Les Plans, Vaud : hind foot, 23 '3 (23-25). 

 Average and extremes of five adults from Cranves-Sales, Haute- 

 Savoie, France : head and body, 138 (135-140) ; tail, 54 (52-57) ; 

 hind foot, 22-5 (22-23); ear, 11-8 (11-12). For cranial 

 measurements see Table, p. 750. 



Specimens examined. — Eighty-two, from the following localities: — 

 Prance : Gerbamont, near Vagney, Vosges, 6 (Lataste) ; Cranves- 

 Sales, Haute-Savoie, 8 ; Lucinges, Haute-Savoie, 4 ; Montauban, Haute- 

 Savoie, 2 ; Scientriers, Haute-Savoie, 1 (Mottaz) ; Etupes, Doubs, 1 

 (Mottaz; not typical). 



