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PSEUDOSTOMA DOUGLASII.-Rich. 
Columbia Pouched-Rat. 
PLATE CV.— Males. 
P. Supra fusca, lateribus subrufis, ventre pedibusque pallidioribus, cauda 
g wporis dimidio longiore.* 
CHARACTERS. 
dbove, dusky brown ; reddish on the sides ; paler beneath and mi the feet ; 
ttx. exceeding half the length of the body. 
SYNONYME. 
Gei -<Y8 Douglasii. Richardson, Columbia Sand-Rat, Fauna Boreali Americana, 
p. 200, pi. 18 B. 
DESCRIPTION. 
Head, large and depressed ; ears, short, ovate, extending beyond the fur ; 
nose, blunt ; nostrils, small and round, separated by a line in the septum ; 
they have a small naked margin. Mouth, of moderate size ; lips, and 
space between the nose and upper incisors, covered with short hair ; 
incisors strong, and slightly recurved ; upper ones with a distinct furrow 
on the anterior surface, near their inner edge ; cheek pouches, large, 
opening externally (like those of all the other species belonging to this 
genus), and lined on the inside with very short hairs. 
The pouches extend from beneath the lower jaw along the neck 
to near the shoulders ; whiskers, short ; body cylindrical, resembling 
that of the mole, and covered with short, dense, velvety fur ; the tail, 
which is round and tapering, although at first sight appearing naked, is 
covered with hair throughout its whole length, but most densely near the 
root ; legs short, and moderately robust ; fore-toes short, the three middle 
ones united at their base by a skin, the outer one smaller and farther 
back ; thumb, very small and armed with a claw ; claws, sharp-pointed, 
compressed, and slightly curved ; palms naked, and on the posterior part 
filled by a large, rounded callosity. The palms in this species are much 
smaller than in P. Bursarius ; the hind-feet are rather more slender than 
