_Records of occurrence._--Specimens examined, 4, from [Cueva del Abra], 6 mi. (by road) NNE Antiguo Morelos. =Tadarida laticaudata ferruginea= Goodwin Geoffroy's Free-tailed Bat 1954. _Tadarida laticaudata ferruginea_ Goodwin, Amer. Mus. Novit., 1670:2, June 28, type from 8 mi. N Antiguo Morelos, Tamaulipas. _Distribution in Tamaulipas._--Known only from southeastern part of state. Specimens from three miles south and 16 miles west of Piedra were found in a crevice inside a cave. Two days previously _Desmodus rotundus_ and _Natalus stramineus_ were obtained from the same cave. All other specimens from the Sierra de Tamaulipas were caught in mist nets. _Nycticeus humeralis_, _Myotis velifer_, _Eptesicus fuscus_, _Lasiurus borealis_ and _L. intermedius_ were taken in nets that also captured _T. laticaudata_. All specimens taken (June 19-23) in the Sierra de Tamaulipas were females, except one. Of 33 females taken, 27 carried a single embryo each, the embryos averaging 27.0 (25-28) mm. in crown-rump length; the other five were lactating. Weight of the pregnant females averaged 16.0 (13-18) grams and that of the five lactating individuals averaged 13.0 (12-14) grams. A male weighed 22 grams. For the taxonomic status of this species in North America see Jones and Alvarez (1962). _Records of occurrence._--Specimens examined, 65: Sierra de Tamaulipas, 2 mi. S, 10 mi. W Piedra, 1200 ft., 27; Sierra de Tamaulipas, 3 mi. S, 16 mi. W Piedra, 1400 ft., 7; 5 mi. S El Mante, 8 (AMNH); 11 mi. S El Mante, 13 (AMNH); 10 km. NNE Antiguo Morelos, 1; 8 mi. N Antiguo Morelos, 7 (5 AMNH, 2 KU); 20 mi. SW El Mante, 2 (AMNH). =Molossus ater nigricans= Miller Red Mastiff Bat 1902. _Molossus nigricans_ Miller, Proc. Acad. Nat. Sci. Philadelphia, 54:395, September 12, type from Acaponeta, Nayarit. _Distribution in Tamaulipas._--Southern part of state, north at least to Guemes. At Rancho Pano Ayuctle, according to the field notes of the collector (Schaldach), the red mastiff bat was common, and found daytime retreats in hollows in cypress trees. Schaldach twice found groups of bats in such hollows. _M. a. nigricans_ is an early forager and most individuals seen were in flight before sunset, usually flying in a more or less straight line at heights of 25 to 60 feet above the ground. The odor of the chest gland was described by Schaldach as "strong" and "geranium-like." A female obtained three miles northeast of Guemes on August 19 carried a single embryo that was 33 mm. in crown-rump length.