NO. 2057. TEE GRASSHOPPER MICE—IIOLLISTER. 453 



intergradation does take place at this point. Aside from the slight 

 difference in shape, there seem to be no actual characters to distin- 

 guish the skuUs of longipes from those of other forms of the Uucogaster 

 group. 



Specimens examined. — Total number, 39, from the following locali- 

 ties: 



Texas: Bee County, 1; Brownsville, 1 (Amer. Mus.); Comstock, 

 3 ; Concho County, 1 (type) ; Corpus Christi, 1 ; Eagle Pass, 1 ; Fort 

 Clark, 8; Laredo, 2; Lomita Ranch, 2; Nueces Bay, 3; Raglan's 

 Ranch, Rio Grande, 1 ; Rockport, 2 (Amer. Mus.) ; San Angelo, 1 ; 

 San Diego, 1 ; Sauz Ranch, Cameron County, 1 ; Sheffield, 25 miles 

 south on Pecos River, 1 ; Sycamore Creek, 1 . 



Tamaulipas: Camargo, 2; Reynosa, 1; Victoria, 2. 



NuEVO Leon: Linares, 3. 



ONYCHOMYS LEUCOGASTER BREVIAURITUS HoUister. 



1913. Onychomys leucogaster hreviauritus Hollister, Proc. Biol. Soc. Washington, 

 vol. 26, p. 216. December 20. 



Type-locality. — Fort Reno, Oklahoma. 



GeograpTiic distribution. — Eastern Nebraska, eastern and south- 

 central Kansas, and middle Oklahoma. From Nehgh, Nebraska, and 

 Fort Riley and Neosha Falls, Kansas, west and south to Kinsley, 

 Kansas, and to Woodward and Fort Reno, Oklahoma. Entirely 

 within the Carolinian and Austroriparian faunas of the Austral region. 



General characters. — Most like 0. I. longipes, but darker and richer 

 colored, with shorter tail, smaller hind foot, and smaller ears. 



Color. — Adult in full winter pelage (96057, Alva, Oklahoma, Feb- 

 ruary 27) : Head and back a rich blackish-brown, the ground color 

 pinkish-cimiamon, the overlying hairs with long blackish tips which 

 streak and darken the ground color; cheeks and sides with less of the 

 dark streaking, the hips and lower rump almost pure pinldsh-cinna- 

 mon. Center of nose gray; cinnamon spots at base of wliiskers, 

 between the gray of nose and white of lips. Ear tufts cinnamon-buff; 

 tail grayish-brown above to near tip, sharply bicolor, the underside 

 and tip white. Arms, hands, lower legs, and entire underparts white, 

 with dark gray underfur everywhere except on chin. Adult in late 

 summer (19145, Fort Reno, Oklahoma, October 8; breeding female, 

 renewal retarded): Upperparts duU grayish-brown; sides brighter, 

 more cinnamon; no conspicuous ear tufts; tail and feet scantily 

 furred. Juvenile (96060, Alva, Oklahoma, September 5): Above 

 hair-brown, finely Hned; sides paler, more drab; no ear tufts; tail 

 brownish above, whitish below. Immature in winter coat (23190, 

 Fort Reno, Oklahoma, December 21): Like the juvenile but darker, 

 more glossy and richly colored; the back blackish-brown, sides more 

 pinkish-buff; no ear tufts; tail brownish above, with white tip; 

 entire underparts white. 



