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 Mexico,
Mexico."
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 Nicolas, 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
Nicolas, which represent the largest series of _M. californicus_ ever
reported from eastern Mexico, some were caught in mist nets and others
were shot over a water-hole.
_Measurements._--Five skins and four skulls from Nicolas
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: Nicolas, 56
km. NW Tula, 5500 ft., 5; 14 mi. N, 6 mi. W Palmillas, 5500
ft., 1.
Additional records: San Jose (Dice, 1937:249); Miquihuana
(Miller and Allen, 1928:160); La Joya de Salas (Goodwin,
1954:5).
=Myotis nigricans dalquesti= Hall and Alvarez