ZOOLOGY. 
129 
These “caches” are capriciously selected. At the cascades of the Columbia I was told by 
a storekeeper that boots, empty kettles, &c., would be chosen, and that he had found in a boot 
a pint of rice, together with other things which had been brought together, grain by grain, and 
bit by bit, by these industrious animals. Like other rats, it is principally nocturnal in its 
habits. 
Before the advent of the brown rat skunks were their principal enemies, who still, where 
they exist, hunt them indefatigably, under and in the houses and outbuildings of the settlers. 
I Avas told that the specimen I obtained, of which the measurements are given beloAV, Avas not so 
large as are sometimes seen. From the appearance of the teeth, &c., of my specimen, I judge 
that it was a full-grown adult. 
Measurements of specimen 149, male , killed at Neio Dungeness , W. T., Straits of Fuca , Jan., 21,1857. 
From nose to occiput. 2.38 inches. 
From nose to base of tail. 9.75 do. 
Tail vertebrae.*. 7.12 do. 
Tail to end of hairy tip. 8.38 do. 
Height of ear posteriorly (from plane of occiput). 1.30 do. 
Hind foot, heel to end of longest claw. 1.75 do. 
Forefoot, heel to end of longest claAv. 1.12 do. 
All the feet, belly, under surface of tail, and inside of legs white. Top of head plumbeous, 
brownish gray. Sides of back brownish gray; middle of back darker. Upper surface of tail 
plumbeous. White hairs of the flanks plumbeous at their bases; those of the middle of the 
breast Avhite to their bases, but tinged Avitli yelloAv on the surface, especially a spot about the 
size of half a dollar around the umbilicus, Avhich is quite of a soiled yellow appearance. The 
settlers say this spot is persistent, being found on all specimens.—S. 
ARVICOLA TOWNSENDII, Bachman. 
Oregon Ground Mouse ; Oregon Salt Meadow Mouse. 
[See Baird, Gen. Kep. p. 527.] 
ToAvnsend’s meadotv mouse, also called the salt-marsh rat, is found on the tide prairies and 
salt meadoAvs bordering Puget Sound. It is A r ery common on the salt meadoAvs along the Straits 
of Fuca, Avbiere, at Ncav Dungeness, I obtained a specimen. On the potatoe fields on the rich 
“bottom lands” in the neighborhood of these marshes they are quite destructive to that vege¬ 
table. The marshes are very much “cutup” by narroAv little trails and paths Avhich they 
travel upon. These are about 2 inches wide and Avell beaten, looking much like buffalo trails 
in miniature. These mice are very numerous at Dungeness, so much so that Mr. Madison in¬ 
forms me that he has killed several hundred in a day while ploughing. 
Measurements of specimen 150, obtained by me at Neio Dungeness January 27, 1857; male. 
From nose to occiput, about. 1.50 inches. 
From nose to base of tail. 5.87 do. 
From base of tail to end of vertebras. 2.56 do. 
From base of tail to end of hairy tip. 2.68 do. 
