Females with embryos or in lactation were collected as follows: Rancho Pano Ayuctle, March 10, one pregnant female (embryo 40 mm. in crown-rump length); Río Sabinas, May 23, two pregnant females (embryos 36 and 43 mm.); Sierra de Tamaulipas, June 13, five lactating females and one female taken alive that gave birth on June 16 to one young; Cueva La Mula, August, nine lactating females. A male from the Sierra Madre that was obtained on January 5 had testes 8 mm. long. The average weight of 21 adults from four miles southwest of Padilla was 39.1 (32.0-44.5) grams. _Records of occurrence._--Specimens examined, 107: 3 mi. W, 6.5 mi. N Jiménez, 1250 ft., 1; Río Soto la Marina, 4 mi. SW Padilla, 800 ft., 23; Cueva La Esperanza, 6 km. SW Rancho Santa Rosa, 360 m., 3; Cueva Los Troncones, 8 km. N, 12 km. W Cd. Victoria, Sierra Madre Oriental, 2500 ft., 2; Cd. Victoria, 1; Sierra Madre Oriental, 1900 ft., 5 mi. S, 3 mi. W Cd. Victoria, 3; La Mula, 13 mi. N Jaumave, 19; Cueva La Mula, 10 km. W Joya Verde, 2400 ft., 16; Joya Verde, 35 km. SW [Cd.] Victoria, 3800 ft., 6; Sierra de Tamaulipas, 1400 ft., 3 mi. S, 16 mi. W Piedra, 10; 70 km. S Cd. Victoria (_via_ Highway), 6 km. W of Highway, 5; Rancho Pano Ayuctle, 6 mi. N Gómez Farías, 300 ft., 7; cave near headwaters Río Sabinas, 10 km. N, 8 km. W El Encino, 400 ft., 11. Additional records (Malaga and Villa, 1957:539): Cueva La Sepultura, 7.5 km. NNW and hence 7 km. SSW (_via_ highway) Cd. Victoria; El Ojo de Agua, at km. 10 on Valles-Tampico highway; Cueva del Abra, 2 km. SSW Cd. Mante. =Diphylla ecaudata= Spix Hairy-legged Vampire 1823. _Diphylla ecaudata_ Spix, Simiarum et vespertilionum Brasiliensium ..., p. 68, type locality, Brazil, restricted to Rio San Francisco, Baía, by Cabrera (Rev. Mus. Argentino Cien. Nat., 4:94, March 27, 1958). _Distribution in Tamaulipas._--Southern and central parts of state. The hairy-legged vampire was first reported from Tamaulipas by de la Torre (1954:114), who recorded a male from five miles northeast of Antiguo Morelos, near El Pachón. Later in the same year Martin and Martin (1954:585) listed another male from El Pachón. Subsequently, Malaga and Villa (1957:543) reported specimens from two additional localities in the state, one of which (Cueva de la Sepultura) provides the northernmost place from which the species has been recorded. Malaga and Villa remarked that the species was abundant at Cueva de la Sepultura, being found in small groups clinging to the roof of the cave. Two females taken there on November 11 carried one embryo each; a lactating female was taken on November 14. The vampire, _Desmodus rotundus_, also was taken at Cueva de la Sepultura. I follow Burt and Stirton (1961:37) in treating _Diphylla ecaudata_ as a monotypic species.