136 



ARVICOLJD.E. MAMMALIA. ARVICOLIDJE. 



FAMILY V. ARVICOLID^. 



The Swimming Arvicoles or Voles are distinguished 

 from the true mice chiefly by the character of the teeth. 

 The incisors are large, chisel-shaped, and coloured 

 deep yellow in front ; the molars have flat crowns pre- 

 senting enamelled folds, in the form of alternating 

 triangles, on either side. The fore-feet are tetradac- 

 tylous, with a rudimentary thumb. The muzzle is 

 obtuse, and the ears are not large. The tail is rather 

 short, rounded, and hairy. 



THE WATER EAT (Arvicola amphibia} has a very 

 close, thick, and shining fur of a rich reddish-brown 

 colour, which becomes paler inferiorly (fig. 46). Its 

 habits are almost too well known to require des- 

 cription. Frequenting the banks of almost every stream, 

 canal, or dyke in this country, it constructs its bur- 

 rows upwards from the water's edge. "It dives 



Fig. 46. 



The AYater Rat (Arvicola amphibia). 



and swims with great facility, instantly seeking the 

 water upon every alarm, and plunging at once to the 

 bottom ; from whence, however, it is obliged to return 

 to the surface for respiration about every minute. It 

 has often been asserted that the water vole lives upon 

 small fish, earthworms, and insects, and it has even been 

 accused of destroying young ducks. There is not, how- 

 ever," observes Mr. Bell, " the slightest foundation for 

 this opinion." It feeds on roots and various aquatic 

 plants. The female produces five or six young at a 

 single birth. 



THE FIELD VOLE (Arvicola agrestis), or MEADOW 

 MOUSE, is about four inches in length, exclusive of the 

 tail, which measures rather more than an inch. Its 

 habits are extremely destructive. It feeds on various 

 vegetable matters, grain, &c., and is particularly fond of 

 carrots. It is very prolific, the female producing from 

 five to seven young at a birth. The best method of 

 destroying these pests is by entrapping them in holes 

 excavated in the ground; these pits should be wider 

 below than above. 



THE BANK VOLE (Arvicola riparia} is, in common 

 with the foregoing, a native of Europe. It is three 

 inches and a quarter long, and the fur is of a bright 

 chestnut red above and greyish beneath. The tail is 



about half the length of the body. It is not very 

 abundant in Britain, and but little is known respecting 

 its habits. 



THE YELLOW-CHEEKED VOLE (Arvicola xantho- 

 gnathus) is an American species, and is abundant in the 

 neighbourhood of Fort Franklin, and also among the 

 Rocky Mountains, especially in localities where the 

 woods have been destroyed by fire. Its habits are 

 similar to those of the common water rat. Length of 

 the body is from five to eight inches. The females 

 produce seven young at a birth. 



WILSON'S VOLE (Arvicola Pennsylvanicus) is, ac- 

 cording to Sir John Richardson, very abundant from 

 Canada to Great Bear Lake. It infests barns and 

 storehouses, where it hoards up grain and seeds of 

 various kinds ; it is said also to be very partial to the 

 bulbs of the Philadelphia lily. The body is about 

 three and a half inches long, the fur being brownish 

 and white underneath. 



RICHARDSON'S VOLE (Arvicola borcalis), or NOR- 

 THERN MEADOW MOUSE, is about four and a half inches 

 long, exclusive of the short tail, which measures only 

 an inch. Its habits are similar to those of the Yellow- 

 Cheeked species. It is found in abundance on the 

 borders of the Great Bear Lake. The fur has a chest- 

 nut tinge mixed with black ; under the belly it is greyish. 



THE SCANDINAVIAN LEMMING (Myodes Lemmus) 

 is about the size of an ordinary rat. The fur is of a 

 ruddy yellow colour, variegated with black. Its proper 

 residence is among the mountains of Norway and 

 Sweden, but it has a remarkable propensity to emi- 

 grate at certain periods. Van der Hoeven remarks, that 

 on these occasions multitudes of them " eat everything 

 bare on the road, like locusts. This usually forbodes 

 a hard winter. The number of these animals thus 

 suddenly appearing in situations where they were pre- 

 viously unknown, gave occasion in former times to the 

 strange opinion that they descended from the clouds." 

 It is sometimes called on this account the NORTHERN 

 MOUSE OF PASSAGE. 



THE GREENLAND LEMMING (Myodes Greenlandi- 

 c?/s) Plate 15, fig. 49 was first described by Dr. 

 Traill, from a specimen procured by the distinguished 

 navigator, Captain Scoresby. The body is six and a 

 quarter inches in length, the tail measuring only three- 

 quarters of an inch. There are no external ears. The 

 fore-feet are hairy beneath, the digital claws being 

 rounded and sharply pointed. The central line of the 

 back is marked by a dark band. The muzzle terminates 

 in a sharp nose. The eyes are near each other, and 

 comparatively small. 



THE HUDSON'S BAY LEMMING (Myodes Hudsonius) 

 is scarcely so large as the preceding, and, according to 

 Richardson, is distinguished by the two central claws 

 of the fore-feet being unusually large ; they are like- 

 wise compressed, " their very blunt extremity being 

 rendered double by a deep transverse notch." Although 

 this species is very easily tamed, very little is known 

 respecting its habits. 



BACK'S LEMMING (Myodes trimucronatus] inha- 

 bits the wooded districts of North America, and is 

 named after Captain Back, who first discovered it on 

 the banks of Point Lake. Sir John Richardson states, 



