1G8 On a new Vole from the Loxer Yang-tse-hici'ig. 



of brain-case above zygomata 12 7 ; lieight of crown from 

 molar level 12*1 ; palate length 15*5 ; length of palatal 

 I'oramina 5'3 ; length of upper molar series 7'5. 



IJah. Lower Yangtse, near Nanking. Sea-level. (Type 

 taken on tlie north bank.) 



Tijpe. Female. B.M. no. 2. 6. 21. 5. Original number 

 10. ' Collected 28th February, 1902, by E. B. Howell. 



From the number of mammaj and sole-pads, the projecting 

 incisors, and other characters it aj)pears to me that M. cala- 

 morum is most nearly allied to the American species placed 

 by Miller with the Old- World water-voles in the subgenus 

 Arvicola. Indeed, its tooth-pattern is by no means unlike 

 that of M. (^Arvicola) macropus, as figured by him in his 

 important work on the subfamily *. The habits of the 

 animal are in agreement with this view of its affinities. 



Perhaps I should myself have been disposed to recognize 

 this " Aulacomys " group as subgenerically distinct from true 

 Arvicola^ but have not worked at the subject sufficiently to 

 express a definite opinion. 



Mr. Howell sends me the following account of the habits 

 of M. calamorum : — 



" This vole is found on both banks of the Yangtze River, 

 and is particularly common around Nanking. It is never 

 found far from water — not that it is aquatic in its habits, but 

 on account of its apparent inseparability from the peaty soil, 

 originally the alluvial deposit of the river, and the reeds 

 which grow there in such profusion. 



" These reeds, which in summer attain a heiglit of from 

 12 to 15 feet, are all cut down in winter. The ground below 

 is dotted with patches of coarse grass, and it is below this 

 grass that the voles for the most part make their burrow. 

 The animals are gregarious in their habits, sometimes covering 

 an area of 15 yards square with their holes. 



" Their food, from an examination of their stomachs and 

 also of their droppings, consists of the usual roots, grasses, 

 &c., and also of the pith of the reeds, of which they must 

 destroy a large quantity. The female produces five or six 

 at a birth. 



" The adult attains a considerable size, one caught by me 

 being 139 millim. from snout to root of tail. 



"Individual varieties are not unknown, as several in my 

 possession show signs of a white patch between the ears {e.g., 

 no. 22). In several, in fact in nearly all large specimens 



* N. Am. Fauna, no. 12, p. G7 (1890). 



