21g CALIFORNIA ACADEMY OF SCIENCES [Proc. 4th Ser. 



Dept. Zool.). California: Humboldt County, Mad River, 

 Big Bend, southeast from Kneeland, Chaparral Mountain, on 

 slope above Maplecreek Post Office, 12; Carlotta, 12; Cudde- 

 back, 1 ; Mendocino County, Mendocino City, 16 (4 in al- 

 cohol) ; Lierly's Ranch, 4 miles south of Mount Sanhedrin, 1 

 (all Coll. Mus. Vert. Zool. Univ. Calif.). 



The writer desires to extend grateful and cordial acknowl- 

 edgment to the following persons : For the loan of speci- 

 mens, to Messrs. H. W. Henshaw and E. W. Nelson, of the 

 Bureau of Biological Survey of the U. S. Department of 

 Agriculture, to Messrs. Richard Rathbun and Gerrit S. Miller 

 of the U. S. National Museum, to Mr. Wilfred H. Osgood, 

 of the Field Museum of Natural History, to Mr. Alfred C. 

 Shelton of the University of Oregon Museum, Department of 

 Zoology, and to Mr. Stanley G. Jewett, of the Oregon Game 

 Department; for identification of lichen used as nest material 

 by the tree mouse, to Professor Williain A. Setchell, Pro- 

 fessor of Botany, University of California; for microscopical 

 examination of nest material to Dr. T. H. Goodspeed of 

 the University of California ; and for much valuable in- 

 formation as to the habits of the tree mouse to Mr. Alfred 

 C. Shelton, of the University of Oregon, to Mr. C. L 

 Clay, of Eureka, California, to Professor Walter K. Fisher of 

 Stanford University, and to Mr. H. E. Wilder, of Carlotta, 

 Humboldt County, California. References in the text to 

 Messrs. Shelton, Fisher, Clay and Wilder are on the basis 

 of their correspondence with the writer. The success of the 

 expedition sent out by the Museum of Vertebrate Zoology to 

 the north coast counties of California, which collected ma- 

 terial representative of Phcnacomys longicaudus and much 

 valuable information regarding its occurrence and habits, is 

 in no small measure due to the following men, who ac- 

 companied the writer, and whose enthusiastic co-operation 

 made the work a pleasure : Mr. Gordon F. Ferris, of Stan- 

 ford University; Mr. Charles L. Camp, of the University of 

 California; and Mr. Alfred C. Shelton, formerly of the Uni- 

 versity of California. 



The writer takes this occasion also to express his apprecia- 

 tion of the valued criticisms and suggestions furnished by Dr. 

 Joseph Grinnell of the University of California under whose 

 immediate supervision the work was carried on. 



