Long-eared bats obtained by field parties from the University of Kansas in the Mexican states of Coahuila, Nuevo León, and Tamaulipas, are found to belong to the species, _Myotis evotis_, but are not referable to any named subspecies. They are named and described as follows:

#Myotis evotis auriculus# new subspecies

Type._–Female, adult, skin and skull; No. 55110, Univ. Kansas Mus. Nat. Hist.; 10 mi. W and 2 mi. S Piedra, 1200 ft., Sierra de Tamaulipas, Tamaulipas; 9 June 1953; obtained by Gerd H. Heinrich, original number 7061.

Distribution._–Coastal foothills and adjacent mountains of northeastern México from central Coahuila south and east to central Veracruz.

Diagnosis._–Size medium (see measurements), ears small for the species; color dark, upper parts (_j_14) Ochraceous-Tawny (color terms are after Ridgway, Color Standards and Color Nomenclature, Washington, D. C., 1912), underparts Warm Buff, ears pale; skull large, teeth large, mandible long.

Comparison._–From _Myotis evotis evotis_ (H. Allen), from Colorado, Wyoming, and Montana, _M. e. auriculus_ differs in: Ears averaging shorter; color darker and richer; ears paler and contrasting less, in color, with pelage; skull larger in all measurements taken except that of least interorbital constriction; forehead, when viewed laterally, rising more abruptly, because frontal region is more inflated; teeth larger.