1890. _V[espertilio]. mexicanus_ Saussure, Revue et Mag. Zool., Paris, ser. 2, 12:282, July, type from an unknown locality, but Dalquest (Louisiana State Univ. Studies, Biol. Ser., 1:49, December 28, 1953) restricted the type locality to the "desert (warmer part) of the state of México, México." 1897. _Myotis californicus mexicanus_, Miller, N. Amer. Fauna, 13:73, October 16. _Distribution in Tamaulipas._--Western mountains of state in pine-oak forest. Only ten specimens of this species, five from Nicolás, two from Miquihuana and the other three, each from a different locality, have been reported from Tamaulipas. The specimen examined from 14 miles north and six miles west of Palmillas, a young female that still has deciduous incisors, was obtained on July 24. Of the five specimens from Nicolás, which represent the largest series of _M. californicus_ ever reported from eastern México, some were caught in mist nets and others were shot over a water-hole. _Measurements._--Five skins and four skulls from Nicolás afford the following measurements: 86.0 (80-94); 39.0 (36-41); 7.4 (7-8.5); 13.7 (13.5-14.0); length of forearm, 33.0 (31.8-34.2); weight, 3.6 (3-4) grams; greatest length of skull, 13.9 (13.8-14.1); least interorbital constriction, 3.2 (3.1-3.3); breadth of braincase, 6.5 (6.4-6.5); length of maxillary tooth-row, 5.2 (5.1-5.3); breadth across M3, 5.1 (5.0-5.3). _Records of occurrence._--Specimens examined, 6: Nicolás, 56 km. NW Tula, 5500 ft., 5; 14 mi. N, 6 mi. W Palmillas, 5500 ft., 1. Additional records: San José (Dice, 1937:249); Miquihuana (Miller and Allen, 1928:160); La Joya de Salas (Goodwin, 1954:5). =Myotis nigricans dalquesti= Hall and Alvarez Black Myotis 1961. _Myotis nigricans dalquesti_ Hall and Alvarez, Univ. Kansas Publ., Mus. Nat. Hist., 14:71, December 29, type from 3 km. E of San Andrés Tuxtla, 1000 ft., Veracruz. _Distribution in Tamaulipas._--Tropical part of state, presently known only from two localities. For taxonomic remarks concerning this bat see Hall and Alvarez (1961:72). _Records of occurrence._--Specimens examined, 5, from 8 km. W, 10 km. N El Encino, 400 ft. Additional record: Cave in canyon of Río Boquillas, 8 km. SW Chamal (Goodwin, 1954:6). =Pipistrellus subflavus subflavus= (F. Cuvier) Eastern Pipistrelle 1832. _V[espertilio]. subflavus_ F. Cuvier, Nouv. Ann. Mus. Hist. Nat. Paris, 1:17, type locality restricted to 3 mi. SW Riceboro, Liberty Co., Georgia, by W. H. Davis, Jour. Mamm., 40:522, November 20, 1959. 1897. _Pipistrellus subflavus_, Miller, N. Amer. Fauna, 13:90, October 16. _Distribution in Tamaulipas._--Presently known only from three localities, but probably occurs in most of eastern part of state.