ZOOLOGY. 
59 
through mountain meadows green as emerald, and daisy-decked, in a region never before pro¬ 
faned by the foot of a white man, and unoccupied by savages, that we found the beaver in num¬ 
bers, of which, -when applied to heavers, I had no conception. The sides of these streams were 
literally lined with their habitations, though we never saw their houses, and seldom a dam 
made by them, but usually their burrows pierced the sides of the stream, a sufficiently large 
and long excavation being made to form warm, roomy, and comfortable quarters. From the 
point where these burrows terminate in the water, trails lead off to thickets of willow or pine, 
where the beavers find their food. These thickets exhibit the most surprising proofs of the 
power and industry of these animals : whole groves of young pine trees cut down within a few 
inches of the ground, and carried off bodily. So well was the work done that one could hardly 
resist the conviction that the woodman’s axe had not there been plied vigorously and well. 
These trees, when felled, are cut into convenient lengths and carried to the burrows, there to 
he stripped of their bark, and then thrown into the stream. We often saw trees of considera¬ 
ble size cut down by the beavers ; the largest which I noticed was a spruce pine twelve inches 
in diameter. 
In California the beaver is also quite common, though less so than in Oregon. It is found in 
the streams flowing into the Sacramento, both from the coast range and from the Sierra Nevada. 
On Cottonwood creek, which comes down from the coast range, near Fort Reading, they abound, 
and have cut the cottonwood trees, which line the banks of the stream, of a diameter of from 
fifteen to eighteen inches. 
To any one who has never seen the beaver in his native haunts the accounts of his mechan¬ 
ical skill and general intelligence, as exhibited in his dams and “clearings,” must seem almost 
fabulous ; and when he has seen these with his own eyes he cannot fail to feel that the pro¬ 
found respect entertained by the Indians and trappers for this sagacious animal is in a great 
degree deserved. 
The value of beaver skins has so much depreciated that they were offered to some of our 
party, by the hale, at twenty-five cents each. 
THOMOMYS BOREALIS. 
Geomys borealis, Rich., Report British Asso. for 1836, V. 1837, 156.—(Said here to come from Saskatchewan.) 
Pseudostoma borealis, Acd. & Bach., N. Am. Quad. Ill, 1853, 198 ; pi. cxlii. 
Geomys townsendii, (Rich. Mss.) Bach., J. A. N. Sc. Phila. VIII, i, 1839, 105. 
Thomomys borealis, Baird, Gen. Rep. Mammals, 1857, 396. 
A single specimen of this very doubtful species was collected at Canoe creek, California. It 
will, in all probability, prove to be only a variety of T. douglasii. 
JACULUS HUDSONIUS. 
Jumping Mouse. 
Dipus hudsonius, Zimmermann, Geographische Geschichte, II, 1780, 358, (based on Pennant’s long-legged mouse 
of Hudson’s Bay.) 
Meriones hudsonius, Acd. & Bach., N. Am. Quad. II, 1851, 251; pi. lxxxv. 
Jaculus hudsonius, Baird, Gen. Rep. Mammals, 1857, 430. 
Sp. Ch.—A bove, light yellowish brown ; lined finely with black ; entire sides yellowish rusty, sharply defined against 
the colors of the back and belly. Beneath, pure white; feet and under surface of tail whitish. Body measuring 2.75 to 
S.50 inches; tail, 4.50 to 6.00 inches; hind feet, 1.10 to 1.30 inches. 
A specimen of this species, collected at Canoe creek, California, agrees with all other western 
ones in a decided superiority in size to eastern ones. 
