MAMMALIA. 
0 
DESCRIPTION 
Of a male, killed at San Bias. 
Form, &c. — Head and feet large in proportion to its body. Eyes large. Nose obtuse. Whiskers 
black, longer than the head. Incisors yellow. Ears rather small, semi-ovate, rounded at the tip and not 
tufted, well clothed on both sides with short hair. Tail long, very hairy, cylindrical or distichous, at 
the will of the animal. Toes long, and well separated. Fore-toes rather slender; third one longest; 
their claws strong, much compressed, short, curved and sharp-pointed ; a small callous wart in place 
of a thumb, protected by a rounded flat nail ; palms naked, with, as usual, five tubercles. The soles 
of the hind-feet are longer and broader in proportion, and are naked much farther back than those of 
Sc. Hudsonius ; they are nearly as long, and are somewhat broader, than those of Sc. capistratus, 
which is a considerably bigger animal. 
Fur, Colour, & c. — Upper surface of the head and back presenting a mixture of pale yellowish - 
brown and black, without spots, the black predominating on the dorsal line ; the forehead sprinkled 
with a few white hairs. Cheeks, flanks, outside of the shoulders and thighs, and anterior surfaces of 
the legs and feet grizzled or hoary, from an equal and intimate intermixture of black and white hairs. 
End of the nose covered with a smooth coat of short, shining, umber-brown hairs. Sides of the nose, 
circumference of the mouth, throat, belly, and insides of the extremities, white. Tail grizzled when 
cylindrical ; having a broad black bar on each side, with a white margin, when distichous. The 
fur of the hack has some lustre on its surface ; its colour, from its roots for three quarters of its 
length upwards, is greyish-black ; which is succeeded by a pretty broad ring of wood-brown, and tipped 
with black ; the black tips of some hairs being much longer than the rest. The hairs of the tail are 
about two inches long; white at the roots and tip, the intermediate part shewing three black rings, 
of which the one next the tip is by much the broadest. At the extremity of the tail there is a tuft of 
long hair, brownish-black to the tip, which is white. 
DIMENSIONS. 
In. L. 
Length of head and body .10 6 
,, of head 2 6 
,, of tail (vertebrae) 8 6 
,, of tail, including fur 11 0 
,, from wrist to tip of middle claw 1 9 
,, of middle fore-toe 0 8 
,, of its claw 0 4 
In. L. 
Length from heel to top of middle hind claw ...... 2 4 
,, of furry part of heel 0 6 
„ of naked sole 1 0 
„ of longest hind-toe and claw 0 9 
Breadth of sole adjoining the toes 0 6 
Height of the ear posteriorly 0 6 
„ of the ear anteriorly 0 8 
55. Geomys Douglasii. Columbia sand-rat. (F. B. A. No. 62.) 
Neighbourhood of Fort Vancouver, on the Columbia. 
56. Diplostoma bulbivorum. The camas rat. (F. B. A. No. 65.) 
Notwithstanding Mr. Schoolcraft’s positive testimony respecting the use and external openings of 
the cheek pouches of the gophers, as referred to in the Fauna Boreali- Americana, doubts on the 
subject, and consequently of the existence of diplostoma as a distinct genus from geomys, have been 
excited since we lately received several specimens of the mus hursarius of Shaw, (which is a true 
geomys, with pouches opening internally,) from the banks of the Saskatchewan. The figure in the 
Linnean Transactions is a correct representation of the form of the animal, and gives the true appearance 
of its cheek pouches when distended with food. They cannot in a recent specimen be made to assume 
the form of the pouches of diplostoma. 
57. Aplodontia leporina. The sewellel. (F. B. A. No. 66.) 
Banks of the Columbia. 
C 
