JEWETT — PHENACOMYS IN OKEGON 
165 
NOTES ON TWO SPECIES OF PHENACOMYS IN OREGON 
' By Stanley G. Jewett 
In the dense forests of the Pacific Northwest, where the sun seldom 
penetrates the heavy growth of firs and spruces to mother earth, live 
two species of the most interesting of our small mammals, Phenacomys 
longicaudus in the tree tops, and Phenacomys albipes on the moss- 
covered floor of the forest. 
Phenacomys longicaudus 
‘From my knowledge of the state of Oregon it seems to me that the 
lower Rogue River watershed in Curry County is the center of abundance 
of these little tree mice. My first visit to this locality was during the 
fall of 1917. One rainy night while talking to two boys about trapping 
the various small fur-bearing mammals of the region it occurred to me 
to ask if they had ever seen ^^a red mouse that lives in trees.” Both 
boys began at once to tell me of their pets that had recently escaped. 
Much to my surprise they had been keeping several individuals of this 
species as pets, and were quite familiar with their habits. I left the 
ranch next morning at daybreak and while passing through the forest 
saw numerous nests of the species in fir and spruce trees, ranging from 
fifteen to eighty feet or more from the ground. Most of the nests were 
saddled on branches against the bole of the tree, but a few were noted 
well out on the branches. 
Most of the nests are fairly compact round balls about twelve to 
eighteen inches in diameter, composed of dry twigs and built by the 
mice occupying them. Other larger and more bulky nests were evi- 
dently built by wood rats and later occupied by these mice. Usually 
they are located in Douglas fir, but several have been noted in Sitka 
spruce near the coast. Two nests in the barn-yard at the John Adams 
ranch in Curry County were built about ten feet from the ground in 
second-growth firs. These nests were as large or larger than a bushel 
basket and composed of dry fir twigs. The trees stood about twenty- 
five feet apart and each was occupied by an adult mouse, which proved 
to be a male and a female. Mr. Adams told me that the nests had been 
there ten years to his knowledge, and as far as he could remember were 
the same as when he located his buildings on the ground. He took it 
for granted they were wood-rat nests, which are very common in that 
locality. These nests were pierced by numerous tunnels leading to 
the inner nests of shredded fir leaves. 
