226 BULLETIN OF THE 



or cream-colored. The latter are preserved in the Springfield Natural 

 History Museum. 



I have known of a few instances of the capture of this species in 

 nearly midwinter. Once a specimen was taken running in the highway 

 early in February, when the snow was a foot and a half deep. They 

 generally leave their burrows very early in spring, often before the 

 ground is fully thawed, but for some time after are irregular in going 

 abroad, and are able to remain six or eight days inside their burrows 

 without food, as they will often do when a trap is set for them. Till 

 the season and vegetation are somewhat advanced they seem to take 

 or require but little nourishment. Later, and especially after the 

 birth of the young in June, they are forced in a much shorter time to 

 leave their holes to obtain food. In fall they become very fat, and 

 early in October generally permanently retire to their burrows, or at 

 least go abroad then much less frequently than earlier, and apparently 

 take very little food. 



The Beaver {Castor fiber Linn.; G. canadensis Kuhl) is to be reck- 

 oned among those i'ew animals that, in this State, have become fully 

 exterminated. 



The few differences pointed out by authors between the European and 

 American beavers, including the distinction based on a comparison of the 

 skulls, are too trivial, in the light of the extensive individual variations 

 now so well known to be almost invariably presented by a large series of 

 specimens of the same species from any given locality, to be taken as satis- 

 factory evidence of their diversity. The weight of authority is also by far 

 in favor of their identity. 



57. Jaculus hudsonius Baird. {Meriones * hudsonius Aud. and 

 Bach.) Jumping Mouse. Rather common, but far from numerous. 



This species has distinct cheek-pouches, — a fact I have not before seen 

 stated. 



58. Mus decumanus Pallas. Broavx Rat. Wharf Rat. 

 Norway Rat. Abundant in the. cities and larger villages generally ; 

 rare or quite unknown in the remote farming districts. 



* Meriones, F. Cuvier, Dents des Mam., 1S25, 1S7; type, Dipus americanus Barton. 

 Not Meriones Illiger, Prod., 1811. 



