1889. _Onychomys longipes_ Merriam, N. Amer. Fauna, 2:1, October 30, type from Concho County, Texas. 1913. _Onychomys leucogaster longipes_, Hollister, Proc. Biol. Soc. Washington, 26:216, December 20. _Distribution in Tamaulipas._--From Ciudad Victoria northward. Only a young female was examined; she weighed 22 grams and extends the known range 59 miles eastward from Ciudad Victoria. _Record of occurrence._--One specimen examined from Soto la Marina, 500 ft. Additional records (Hollister, 1914:253): Camargo; Reynosa; [Cd.] Victoria. =Onychomys torridus subrufus= Hollister Southern Grasshopper Mouse 1914. _Onychomys torridus subrufus_ Hollister, Proc. U. S. Nat. Mus., 47:472, October 29, type from Miquihuana, Tamaulipas. _Distribution in Tamaulipas._--West of Sierra Madre Oriental. The six specimens examined were collected in the desert area west of the Sierra Madre Oriental. At Nicolás a trap set in front of a hole held one specimen, and another was trapped beneath a brush fence that inclosed a cornfield. _Dipodomys merriami_ and _Perognathus penicillatus_ also were trapped beneath the fence. A subadult from Nicolás is slightly larger (see measurements) than either of two subadults from four miles north of Jaumave and an old specimen from eight miles north of Tula, except in the interorbital constriction, which is narrower. Nevertheless measurements of Tamaulipan _Onychomys torridus_ resemble those given by Hollister (1914:483) for _O. t. subrufus_. A specimen from Nicolás is also darker than other individuals examined. A female taken on July 15, four miles north of Jaumave, was lactating. _Measurements._--Measurements of a female from Nicolás, a male from eight miles north of Tula, and a female and a male from four miles north of Jaumave are as follows: 158, 147, 145, 144; 59, 58, 55, 55; 22, 21, 22, 22; 21, 20.5, 18, 18; condylobasal length, 24.4, 23.1, 23.9, 23.7; interorbital constriction, 4.1, 4.4, 4.3, 4.5; length of nasals, 10.6, 10.5, 10.5, 10.1; length of maxillary tooth-row, 3.8, 3.6, 3.7, 3.7; breadth of braincase, 11.8, 11.3, 11.3, 11.0; weight in grams, 32.5, 26.0, 25.0, 25.0. _Records of occurrence._--Specimens examined, 6: 4 mi. N Jaumave, 2; Nicolás, 56 km. NW Tula, 5500 ft., 2; Tajada, 23 mi. NW Tula, 5200 ft., 1; 8 mi. N Tula, 4500 ft., 1. Additional records (Hollister, 1914:475): Miquihuana; Jaumave. =Sigmodon hispidus= Hispid Cotton Rat