An Oregon Mouse. 241 



leaves and twigs, on a limb some six inches in diameter and about 

 six feet from the body of the tree. On felling the tree about a year 

 before he had captured one, which unfortunately had not been pre- 

 served. Of course I requested him to obtain one for me if possible, 

 with the result that last summer, while in Coos county, he secured 

 the specimen on which the species is based. 



My first discovery of this animal was in June, 1886, in the val- 

 ley of Elk Head, on the head waters of Elk creek, a tributary of the 

 South Umpqua river, and some seven miles east of Voncalla, Douglas 

 county, while out looking for birds' nests. I saw a nest which I 

 took to be an old bird's nest, on the upper side of a branch in a 

 clump of twigs some thirty feet from the ground. On throwing a 

 stick at it to ascertain its character, I was surprised to see a mouse 

 run out of it upon a twig, where it stopped. I threw again and 

 succeeded in dislodging the little fellow, which, on capturing, I at 

 once recognized as something new. I kept it for some time alive, 

 secured the nest, and soon after sent it, with measurements, to the 

 Smithsonian Institution, but unfortunately the package was lost, 

 and I failed to secure another until the one described by F. W. True. 

 I have, however, found their nests down Elk creek, along the Co- 

 quelle river, in Coos county, in southern Douglas county, and also 

 on the upper Willamette tributaries, in Lane county, and believe it 

 will yet be found in Washington and perhaps through the whole of 

 the northern Pacific coast. 



The nest is a novelty in itself, being about the size of a robin's 

 nest, and built after the usual manner of mice in shape, but almost 

 exclusively of the leaves of the tree in which it lives, which are split 

 into threads from end to end, forming very slender filaments, sel- 

 dom broken, and each leaf is frequently split twice or more, making 

 from two to four threads of each leaf. These threads are soft, dry 

 and apparently warm, and they show much ingenuity in the general 

 make-up of the whole nest. Rarely has a few unsplit leaves, moss 

 and twigs on the outside of the nest been found. 



For some reason which I have not been able to discover, these 

 nests seem to be frequently changed or deserted, from the fact that 

 we frequently find in the woods and under lone trees of this variety, 

 on the ground, small parts and at some times almost, as it appears, 

 the entire nest ; and I know of no other animal that has been known 

 to split the leaves of this tree, as this one certainly does. 



As to the food of this animal I can only surmise, as I did not 

 dissect the only specimen I ever saw in the flesh, nor have I any clue 

 farther than its habits of living in trees, but think it must subsist 

 on the fruit of the tree, which is usually in fruit more or less all the 



