416 VERTEBRATA. 



tribes, the Saccophoriens and Saccomyens. We shall notice them under six genera, the two first 

 of which belong to the Saccophoriens, and the four last to the Saccomyens. 



Gams SA( '< '( >1'1H >Itl'S : Saccophorus. — This term — which is nearly synonymous with the 

 ]'s, udostoma of Say, the Qeomys and Diplostoma of Rafinesque, the Ascomys of Lichtenstein, and 

 the Saccomys of F. Cuvier — means Sack-/l<<in r, and includes various small animals found from 

 Canada to Mexico. They are partially nocturnal, hibernate, and become somewhat dormant in 

 winter, in cold but nol in warm countries, and use their cheek-sacks or pouches, which generally 

 open externally, for the purpose of bringing food to their burrows. They are all vegetable eaters. 



The Canada Poi chbd-Rat, or the Pi rsed-Saccophorus, S. bursanus, is of a reddish-brown 

 r above, and dark-brown below; the body, which, is stout and cylindrical, is seven or eight 

 inches long, the tail two and a quarter. The cheek-pouches, one on each side, open externally, 

 so that food in the pouches has to be taken out and carried round to the mouth; they are very 

 large, being three inches deep, and lined with hair. The eyes are small, the cars short and hardly 

 visible. The fur is thick and soft. It digs extensive burrows in sandy places, much in the man- 

 ner of the mole, though lower down. At distances of some twenty yards apart, it has openings, 

 usually near some spot covered with grass or vegetables. It sometimes frequents gardens, where 

 it eats the roots of the plants and gnaws the bark of the peach-trees. Sometimes it destroys large 

 numbers of fruit-trees, plums, pears, and apples. The pouches are used to convey food to its bur- 

 rows; it can travel nearly as fast backward as forward ; it bites severely, and resists an attack 

 uttering sharp screams. These creatures fight among themselves with their snouts like hogs. They 

 feed sitting on their rumps, using their fore-paws like hands; they clean their hair, whiskers, and 

 body like rats and squirrels. They feed on vegetables of various kinds; the nest is usually rounded, 

 formed of soft substances, lined with the hair of the female, and is placed in the center of several 

 converging galleries. The young are five to seven at a birth, and are produced in March or April. 

 This species is found in Canada, and thence westward to the Pacific, and southward, in certain lo- 

 calities, to Arkansas. It is common in Illinois and Missouri; at the latter place it is called Mulo. 



There are many other species of pouched rats in North America, but the only ones mentioned 

 by Gervais under this genus are the S. Mexican/is and S. Bottce, the first found in Mexico and the 

 last in California. M. Leconte, in a recent work, enumerates eleven species for the United States 

 and Mexico, arranging them under the genus Gcomys. Other writers notice the following under 

 the generic name of PSEUDOSTOMA, including those mentioned by Gervais and Leconte. The 

 cheek-pouches, generally, open outside of the mouth. 



The Columbia Pouched-Rat, P. Douglassii — the Columbia Sand-Rat of Richardson — is six 

 inches and a half long, is of a dusky-brown color, and of a lighter shade beneath. It is found west 

 of the Rocky Mountains, from the sources of the Missouri to Fort Vancouver. It burrows in the 

 sand-hills, and feeds on nuts, acorns and grasses; in the vicinity of the settlements it commits 

 great havoc in the potato-fields, alike by eating and carrying off in its pouches large quantities 

 of the potatoes. 



The Mole-shaped Pouched-Rat, P. taljxndes, is grayish-black, seven inches long, and is foimd 

 from Hudson's Bay to the Saskatchewan. 



The Camas Rat, P. Borcalis — the Gcomys Townsendii of Richardson — is called Gauffre by 

 the French, and hence Gopher by the Americans, a term also applied to several other species; 

 it is of a pale yellowish-gray, seven and a half inches long, and derives its common name from 

 its fondness for the Quamash or Camas plant, Scilla cscalata. It is exceedingly voracious, and. 

 like all other pouched-rats, feeds on nuts, roots, grasses, and seeds, and makes burrows, not far 

 beneath the Burface of the ground, to a great distance. It is said that in digging its burrov 



uses its larvv el k-pouches like bags to bring up the earth, emptying them at the mouth of the 



burrow. Like- others of this tribe it is to a certain extent gregarious, many of them being always 

 found in the same locality. This species is common near the Columbia River in Oregon. , 



The Southern PoucHEn-RAT, P. Floridana, is of a brownish-yellow above and gray beneatli ; 

 its length is between eight and nine inches. It resembles the Canada pouched-rat, and is prob- 

 ably the species named the Georgia Hamster by Rafinesque and others. Its cheek-pouches, how- 

 ever, open into the mouth. It is found in Florida, Georgia, and Alabama. 



