NO. 2057. THE GRASSHOPPER MICE—H0LLI8TER. 441 



Mexico, show a decided approach toward ruidosx, and specimens from 

 Paladora Canyon, Texas, are strongly tending toward hreviauritus. In 

 general, however, the race is well defined and occupies the greater 

 part of the arid Upper Sonoran region of the Great Plains. 



Specimens examined.— Total number, 331, from localities as follows: 



South Dakota: Bonesteel, 1; Buffalo Gap, 1; Corral Draw, 1 

 (Amer. Mus.); Minniechaduza River, 1; Pine Ridge, 2; Smith ville, 

 1 ; South fork White River, 1 ; Stanley County, 1 (State Biol. Surv. 

 S. Dak.). 



Wyoming: Aurora, 1 (Amer. Mus.); Big Sandy, 7; Bitter Creek, 20 

 (Amer. Mus. and Field Mus.); Bordeaux, 1; Bridger Creek, 1; Bridg- 

 er's Pass, 2; Bull Lake, 1; Casper, 5; Cheyenne, 1; Chugwater, 1; 

 Cumberland, 1; Fontenelle, 4; Fort Bridger, 1; Green River, 1; Grey 

 Bull, 1; Kemmerer, 3; Kinney Ranch, 2; Medicine Bow Mountains, 

 1; Mountain View, 4; Newcastle, 1; Owl Creek Mountains, 1; Sara- 

 toga, 4; Sun, 5; Superior, 1. 



Nebraska: Birdwood Creek, 2; Callaway, 4; Cherry County, 1; 

 Cody, 2; Fort Niobrara, 1; Haigler, 5; Kennedy, 7; Lakeside, 4; 

 Lincoln County, 3; Mitchell, 6 (Univ. of Nebr.); Myrtle, 2; Niobrara 

 River, 12; Perch, 19 (Amer. Mus. and Field Mus.); Snake River, 1; 

 Thomas County, 4; Valentine, 9; Warbonnet Canyon, Sioux County, 

 4 (Univ. of Nebr.). 



Colorado: Burlington, 2; Canadian Creek, 5; Canon City, 1; 

 Cheyenne WeUs, 1 (Amer. Mus.); Colorado Springs, 16 (Field Mus., 

 Amer. Mus., Um\ . of CaUf ., and Mus. Comp. Zool.) ; Denver, 1 (Amer. 

 Mus.); Gaume's Ranch, Baca County, 1; Golden, 1; Greeley, 2; 

 Higbee, 1; Hugo, 2; La Jimta, 1; Las Animas, 1; Lay, 1; Limon, 2; 

 Loco, 2; Longmont, 1; Loveland, 14; Monon, 1 (Mus. Comp. Zool.); 

 Pawnee Buttes, 2; Roggen, 1; Sahda, 1; Snake River, 2; Sterlmg, 

 3; Three Forks, 1 (Amer. Mus.); Wray, 3 (Amer. Mus.). 



Kansas: Colby, 5; Ellis, 1; Logan County, 6 (Amer. Mus. and 

 Kans. Univ.); Meade, 1; Pendennis, 9; Trego Coimty, 15. 



Texas: Amarillo, 1; Fort Lancaster, 1; Hereford, 2; Lipscomb, 

 12; Mami, 1; Mobeefcie, 1; Monohans, 2; Paladora Canyon, 2 (Field 

 Mus.); Texline, 12; Washburn, 2. 



New Mexico: Carlsbad, 4; Clapham, 4 (Phila. Acad. Sci., includ- 

 ing tyi^e; Mus. Comp. Zool.); Clayton, 1; Fort Sumner, 2; Koehler 

 Junction, 1; Roswell, 6; Santa Rosa, 6. 



ONYCHOMYS LEUCOGASTER BREVICATTDXTS Merrlam. 

 1891. Onychomys leucogaster brevicaudus Merriam, North Amer. Fauna, No. 5, 

 p. 52. July 30. 



Type-locality. — Blackfoot, Bingham County, Idaho. 



Geographic distribution. — Southern Idaho, extreme southwestern 

 Wyoming, northwestern Utah, and west across the northern half of 

 Nevada into Lassen, Plumas, and Mono Counties, California. 



