THE COMMON HAMSTER. 343 



that behind the cheeks, the latter spot being continued towards 

 and round the mouth ; the cheeks and regions round the ears 

 are of a russet colour -, the feet are white. The belly is black. 

 In several neighbourhoods in Germany, there is a black variety 

 of the hamster, with only the nose and feet white -, and a mixed 

 breed of the common and black variety is said to exist, and 

 to be grey. Albinoes are very scarce, but have been occa- 

 sionally found. The teeth are sixteen in number, twelve of 

 which are molars, the rest incisors. The animal has two 

 membranous cheek-pouches, which have a wide communication 

 with the cavity of the mouth, from whence they extend between 

 the skin and muscles, along the neck and shoulders, in a 

 somewhat converging direction, so that the shut ends are nearer 

 each other than the open ones in the cavity of the cheek. 

 " Their outer surface," Dr. Weissenborn says, "is perfectly 

 smooth, but the inner one is closely covered with longitudinal 

 and parallel dotted lines, the dots being almost square, and 

 constituting mucous cells or glandules ; wherefore the inside of 

 the pouch is constantly wet and smooth, or it would easily be 

 torn by its contents, which often present rough or sharp surfaces. 

 Between their two attachments these pouches, when empty, 

 extend like two loose narrow canals ; but when dilated, they are 

 oval, two inches and a half in length, and one and a half in 

 breadth, wherefore their periphery, where it is widest, measures 

 about five inches and a half. When these pouches are full of 

 food or inflated by the animal, its head and neck look twice as 

 broad as usual. In each of these pouches the hamster can con- 

 veniently carry home about an ounce and a half of corn, or the 

 same quantity of green fodder. It empties them by stroking 

 them from behind with its fore-paws ; a rather strong muscle 



* The badger also has the belly of a black colour ; a coincidence deserving 

 physiological investigation, as both that and the hamster are crepuscular, 

 subterranean, and winter-sleeping animals. " The cause of this peculiar 

 coloration of these two animals," Dr. Weissenborn says, " may perhaps be 

 traced to some general law of nature, especially as the mole, which is strictly 

 subterranean, is altogether black, although the exclusion of light be, in 

 general, a hinderance to the development of pigments." 



