92 MAMMALIA ORDER V.RODENTIA. 



may be either of medium length, or reduced to a stump. The coloration, 

 which is never like that of the chipmunks, may be either uniform or striped. 

 In habits, the susliks are social and burrowing animals, selecting dry sandy 

 soil for their underground habitations ; and in the colder portion of their 

 range hibernating during the inclement months of the year. The common 

 American species is the striped gopher ($. tridecemlineatus). Susliks agree 

 with the two following genera in that the incisor teeth lack the compressed 

 form characterising those of the squirrels and their immediate allies, and also 

 in the simple structure of their molars. The prairie-marmots, or prairie- 

 dogs (Cynomys) of North America form in some respects a connecting link 

 between the susliks and the true marmots, being intermediate in size between 

 the two, and having stouter bodies than the former. Their ears are small, and 

 the tail is generally short, while their cheek pouches are less capacious than 

 those of the susliks, and the first toe of the fore-feet is well developed, and 

 carries a large claw. The massive skull has the large postorbital processes 

 directed nearly outwards, and the stout molar teeth, which form two series 

 converging behind, differ from those of both the susliks and marmots in 

 having three, in place of two grooves, on their crowns. In habits the prairie- 

 marmots very closely resemble the true marmots, but the mounds of 

 earth they throw up from their burrows have a very distinct crater-like 

 form. 



From the prairie-marmots the true marmots (Arctomys) may be distin- 

 guished by their stouter form, the absence of cheek pouches, the rudimental 



first toe of the fore-foot, which carries only a 

 small flat nail, and the above-mentioned 

 differences in the form and direction of the 

 upper molar teeth. Marmots are common to 

 the northern half of both the Old and New 

 World, ranging as far south as the Pyrenees, 

 Alps, and Himalaya. They are among the 

 larger members of the order, the common 

 Alpine marmot measuring more than 20 

 inches in length, exclusive of the tail. In 

 appearance they are stoutly built, with short 

 legs, powerful claws, a broad and short head, 

 small and rounded ears, and a bushy tail, usually 

 less than half the length of the body. Their 

 fur is moderately long, and somewhat stiff ; 

 while their colour exhibits various tints of 

 Fig. 56.-C OMM o N MARMOT g lden ? r reddish-brown, shading, more or 



(Arctomys mannotta). less markedly into black along the back and 



tail, the tip of the latter being always 



blackish. As regards their habits, marmots live in extensive societies, their 

 large and deep burrows forming warrens, and communicating with one 

 another underground. All the regions they inhabit experience a very severe 

 winter climate, during which the marmots hibernate securely in the depths 

 of their burrows, only waking from their long sleep at the melting of the 

 snows. Those that dwell in the mountains of Europe and Asia generally 

 select open valleys or uplands, where the soil is more or less sandy, for the 

 construction of their burrows, the neighbourhood of water being essential. 

 In Russia and Siberia they inhabit the open and barren steppes. Extreme 

 wariness, especially where they dwell on frequented routes, is characteristic 



