CLASS I. MAMMALIA: ORDER Y. RODENTIA. 
431 
yellowish-white ; some are also marked with white on the ordinary color. It is common in all 
parts of Europe, and despite its small size, is the scourge of the farmers. It lives in cultivated 
plains, especially in the grain-fields. In summer it attacks the cereals, cutting down the stalks to 
get the ears ; when these are harvested it eats the roots of grass, and especially those of the young 
clover; it then makes an onslaught upon the carrots and other leguminous vegetables; when au- 
tumn approaches it devotes itself to the seeds. AVhen the earth is frozen it migrates to the barns, 
and revels among the hay and grain. Some seasons — that is, about once in five years — the num- 
bers are so great as to become devastating to the harvests; at other times they are more rare. It 
has been estimated that in La Vendee, in France, during the years 1816 and 1817, they destroyed 
crops to the value of three milhons of francs, and they were equally destructive in some other 
parts. They are very unequally distributed, in some places being abundant, in others sparsely 
scattered over the country. Italy is said to be the only part of Europe where they are not found. 
They extend into Siberia as far as the Obi. They are most common in the plains, but are found in 
mountainous countries, even so high as the hospital of Mt. St. Gothard, 6,000 feet above the level 
of the sea. This little creature is gentle, soft, graceful, but as it feeds on the same things that 
man feeds on, and as, moreover, it takes without liberty the fruits of man's labor, it is everywhere 
an object of hatred. Millions of them are destroyed by the inundations which take place in 
countries traversed by mountains, and other millions are destroyed by the agency of man. Small 
and insignificant as it is individually, on account of its immense numbers i-t forms the staple ar- 
ticle of food to innumerable hawks and herons, cats, weasels, owls, and other flesh-eaters ; and 
thus it performs a considerable part in the great theater of animal life. 
The A. agrestis, called A. neglecta by Thompson, and A. arenicola by Selys, is a large species, 
found in Scotland and the northern parts of Europe. This is to be distinguished from the A. 
agrestis of the Penny Cyclopedia and other authorities, which give this title to the A. arvalis. 
The A. fulvus is of the size of the preceding, and is sometimes found mingled with it. It is a 
native of the western parts of France and of Belgium. The A. incertus, A. Selgsii, A. glao-eolus, 
A. JVagerij A. Savii ; the A. suhterraneus^ A. socialis, A. osconomus, A. duodecim costahis, A. ru- 
bidus, A. leiicurus, A. nivalis, and A. terrestris, are all European species, bearing a general resem- 
blance to the common field-mouse, but less numerous and less generally distributed. 
The Water-Rat, or Water-Yole, Mus amphihius^ or aquaticus, is about the size of the black 
rat, from which it is easily distinguished by its larger head, its shorter tail, and its more rufous tinge. 
It is about five inches long, and the tail half that length. Its fur is soft, and of a slightly reddish- 
brown above and deep ash-color below; the tail is covered with rough scales. It is fond of the Avater, 
and swims well, though its feet are not palmated. It is found along the borders of rivers, lakes, 
and streams, as well as of bays and lagoons connected with the sea. It breeds twice a year, 
and produces six to eight at a birth. It feeds on vegetables, and is found in various parts of 
Europe. 
The A. destructor, or A. Musignani, is of the size of the preceding, and differs from it but little 
in appearance. It is common in Italy, and especially in Tuscany, where it is a national pest. It 
is said that in 1837-8 this species being driven from their retreats by inundations in this country, 
spread themselves over the cultivated lands and destroyed four-fifths of the crops. When an at- 
tempt was made by the government to redeem the Maremma marshes by dykes, these creatures 
presented almost fatal obstacles by eating the roots of the trees and slirubs planted upon them in 
order to protect them. The A. monticola resembles the preceding, and inhabits the Pyrenees. 
We now proceed to notice very briefly the common species of American Arvicola. AVilson's 
Meadow-Mouse, a. Pennsylvanica, is brownish-fawn above and grayish-white beneatli ; fur long 
and fine ; length five inches, tail one and three-quarters. It is found in all the meadows of the 
United States, where it traces winding, shallow paths in the earth among the grass leading to and 
from its nest, usually in a stump, or some little elevation along a ditch. If the soil is here dug up, 
the mouse and its family of six to ten individuals may be found. The food of this species consists 
of roots, bulbs, grasses, and in the season, of seeds, those of the red-top and herds-grass being among 
its favorites. It does not invade the upland grain-fields, but when the winter has destroyed or 
locked up the roots on which it usually subsists, it attacks the stems of shrubs and fruit-trees, and 
