94 Zoological Society :— 
face of the water. His habits very nearly approximate those of the 
Beaver: he swims about boldly in the day-time, but dives rapidly 
on the approach of danger. If a dead or badly wounded duck be 
left on the pool, it is at once seized on, towed into the house, and 
devoured. 
I am quite satisfied, from careful observation, that the Musk Rat 
is a carnivorous beast whenever he has a chance; and the straight, 
sharp-cutting, strong incisor teeth are well adapted for the indul- 
gence of such propensities. 
If there were no rushes growing where the mud-rover lived, it 
might be assumed that he dug a hole into the bank from lack of 
material to build a house; but I have often seen the rushes growing 
abundantly where he ‘has chosen his mud hut, offering every facility 
for architectural pursuits, had he so willed. On the other hand, had 
the rush-builder been precluded from finding a mud-bank in which 
to construct his mansion, it might have been supposed that he had 
resorted to making a hut with rushes on that account. 
This Lagomys, which I propose making a new species, and calling, 
from its being so much less than any other, Lagomys minimus, lives 
on the summit of the Cascade Mountains, at an altitude above the 
sea-level of about 7000 feet. He chooses as his residence loose piles 
of rocks and stones. He is shy and wary, and on the slightest noise 
takes a header into a crevice. When everything is again still and 
quiet, he cautiously peeps out, and, growing bold in the silence, climbs 
up on the top of astone, and, sitting on his hind legs like a begging 
dog, gives a sharp shrill cry; and so curiously deceptive is it that I 
constantly imagined the sound was far distant when it has been close 
to my feet. It was in October, when I was on Ptarmigan Hill, a 
high mountain in the Cascade range ; the snow was just beginning to 
fall ; and all these little fellows were then busily employed in making 
large nests, in the crevices between the stones, of dry grass and leaves, 
evidently for their winter sleep, and perhaps store-house. I should 
have made much more extensive observations, had not the prospect 
of coming snow driven me down. 
This Lagomys, which is much larger, and which I believe to be 
the same as the one described and figured by Sir J. Richardson (pl. 19) 
as Lepus (Lagomys) princeps, I first saw at Chilukweyuk Lake, a 
large lake on the west side of the Cascades, close to the boundary-line, 
and next on the trail leading from Fort Hope on the Fraser River 
to Fort Colville on the Columbia, both fur-stations of the Hudson’s 
Bay Company. The animals were in a narrow gorge, among large 
heaps of loose stones that had rolled down from the high precipitous 
sides of the gorge. I saw them busily feeding on grass, much after 
the fashion of a rabbit, eating a few mouthfuls, then stopping and 
sitting up and quietly taking a survey of things in general. At this 
period, later in the year, about the same date at which in the year 
preceding I had seen Lagomys minimus making its nest, not a trace 
of a nest could I see, nor any evidence of an attempt to make one. 
It was at the same period of the year, and about the same altitude, 
that I saw this Lagomys at Chilukweyuk Lake; but no nest, nora 
