J38 CALIFORNIA ACADEMY OF SCIENCES [Proc. 4th Ser. 



to whom credit belongs for first calling the attention of sci- 

 entists to the species, asserts (1891, p. 241) concerning its 

 occurrence: "My first discovery of this animal was in June, 

 1886, in the valley of Elk Head, on the headwaters of Elk 

 Creek, a. tributary of the South Umpqua River, and some 

 seven miles east of Voncalla, Douglas County [Oregon], while 

 out looking for birds' nests .... I have . . . found 

 their nests down Elk Creek, along the Coquelle 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 coast." Maps of Oregon, which the writer has 

 examined, show two Elk Creeks tributary to the Umpqua 

 River. Elk Head is located on the Elk Creek tributary to 

 the main river, not tributary to the South Fork of the 

 Umpqua. Voncalla is spelled Yoncalla on recent maps 

 (1908, 1910), and Coquelle is rendered Coquille on the 

 same maps. 



In the original description of Phenacomys longicaudus 

 (True, 1891, pp. 303-304) there is quoted a letter from Todd 

 in which is contained the only reference I have seen to the 

 occurrence of the tree mouse in Curry County. 



Mr. Alfred C. Shelton, field naturalist of the University of 

 Oregon, tells me that he has located colonies in the vicinity 

 of Mabel, Lane County, and Melrose, Douglas County; while 

 Mr. C. L Clay, of Eureka, California, writes that on June 16, 

 1915, he observed a number of Phenacomys nests along the 

 road between Ferndale and Capetown, on the ridge just north 

 of Cape Mendocino and very close to the coast. 



Upon this showing it is not unlikely that the species is 

 far more abundant and widespread than the examples now 

 contained in museums would indicate. 



n Habits 



1. GENERAL HABITAT 



Characteristically, perhaps exclusively, arboreal. That the 

 tree mouse ever comes to the ground of itself for the pur- 

 pose of subserving its own specific economy remains to be 

 demonstrated. In Todd's letter of transmittal which ac- 



