31° 47'; Long. 30° 15', 13 (USNM). _Eddy County_: 3 mi. NW Carlsbad, 7 (MVZ); 2 mi. E Carlsbad, 1 (KU); Eddy, 10 (USBS). =Texas=: _El Paso County_: 3 mi. NE City Limits, El Paso, 3764 ft., 15 (12 MVZ; 3 TCWC); El Paso, 3 (USBS); near El Paso, 7 (USNM). _Hudspeth County_: 1 mi. NW old Fort Hancock, 3900 ft., 3 (MVZ); Fort Hancock, 4 (USNM); 4 mi. NW Sierra Blanca, 1 (LACM). _Culberson County_: 35 mi. N Van Horn, 5 (TCWC); 30 mi. N Van Horn, 1 (TCWC); 16 mi. E Van Horn, 3 (TCWC); 16 mi. SE Van Horn, 5 (TCWC); Kent, 1 (USBS). _Reeves County_: 5 mi. E Toyahvale, 1 (USBS). _Jeff Davis County_: 14-1/2 mi. S Fort Davis, 2 (UM). _Presidio County_: 10 mi. NE Marfa, 1 (UM). =Sonora=: Nogales, 2 (USNM); Santa Cruz, 4 (USNM); 5 mi. N Cananea, 4750 ft., 4 (MVZ); Alamo Wash, 35 mi. NW Magdalena, 5 (DRD); Sonora, 2 (AMNH). =Chihuahua=: 4.3 mi. W Casas Grandes Viejo, 5000 ft., 8 (MVZ); 1.5 mi. W Casas Grandes Viejo, 1 (MVZ); Casas Grandes, 2 (USBS); Gallego, 1 (USBS); Colonia Diaz, 6 (USBS); Las Trincheras, 9 mi. S by road Boquillos de Condios, 4 (MVZ); Santa Rosalia, 6 (USBS); Chihuahua, 7 (USBS); 5 mi. SE Chihuahua, 5250 ft., 4 (MVZ); Corallitos, 4 (1 USBS; 3 MVZ). =Dipodomys ordii luteolus= (Goldman) _Perodipus ordii luteolus_ Goldman, Proc. Biol. Soc. Washington, 30:112, May 23, 1917. _Dipodomys phillipsi ordi_, Coues and Allen, Monogr. of N. Amer. Rodentia, p. 541, August, 1877 (part--the part from Niobrara River, Nebraska). _Perodipus montanus richardsoni_, Cary, N. Amer. Fauna, 33:141, August 17, 1911 (part--the part from Sterling, Colorado). _Dipodomys ordii luteolus_, Grinnell, Journ. Mamm., 2:96, May 2, 1921. _Type._--Male, adult, no. 160408, U. S. Nat. Mus. Biol. Surv. Coll.; Casper, Natrona County, Wyoming; obtained on September 2, 1909, by Merritt Cary, original no. 1690. _Range._--Southeastern Wyoming, northeastern Colorado, northwestern half of Nebraska and southwestern South Dakota; marginal occurrences are: in Wyoming, Casper, Sun and Ft. Steele; in Colorado, Loveland, Hugo and Akron; in Nebraska, Birdwood Creek, Neligh and Valentine; in South Dakota, Batesland and Buffalo Gap. _Diagnosis._--Size medium (see measurements). Color light, entire dorsal surface between Light Ochraceous-Buff and Ochraceous-Buff, purest on sides and flanks; upper parts but lightly washed with black; arietiform markings, plantar surfaces of hind feet, pinnae of ears and dorsal and ventral stripes of tail, blackish. Skull medium in size; jugal weak; braincase slightly inflated; nasals slightly flared distally.