FIELD BOOK OF MAMMALS 



Le Conte Free-tailed Bat. — Tadarida cynocephala (Le 



Conte) . 

 As described above. Found in the southeastern states 

 from Georgia and southern Alabama south and west ; limits 

 of range unknown. 



Mexican Free-tailed Bat. — Tadarida mexicana (Saussure). 

 Resembling cynocephala in external characters. Upper- 

 parts hair-brown, paler on underparts. Total length, 4 

 inches; tail vertebrce, 1.3 inches; hind foot, .4 inch; forearm, 

 1.7 inches. Found in the southwestern United States from 

 Garfield County, Colorado south into Mexico and from 

 the Pacific east to the middle of Texas. 



Pocketed Bat. — Tadarida femorosacca (Merriam). 



Similar to mexicana but larger, tail more than half free of 

 membrane, a fold of membrane from femur to tibia forming 

 pocket. Upperparts dull brown. Total length, 4.1 inches; 

 tail vertebrae, 1.6 inches; forearm, 1.6 inches. Very few 

 specimens of this Bat have ever been taken. The only 

 records I have seen are Palm Springs, Riverside County, 

 Palm Canon near Palm Springs, California, and Fort 

 Huachuca, Arizona. 



Tacubaya Free-tailed Ba.t.~~Tadarida depressa (Ward). 



Size large; ears united at bases; prominent swelling between 



eye and nostril. Upperparts dull brown ; underparts lighter. 



Total length, 5.6 inches; tail vertebrae, 1.60 inches; hind 



foot, .52 inch; forearm, 2.4 inches. Found from Mexico 



City north to Iowa, but has been collected only a few times. 



There are records from Arizona, Nevada, Colorado, Iowa, 



and California, one specimen each, except for Iowa two. 

 ******* 



The Free-tailed Bats are easily recognized by the mouse-like 

 tail which projects beyond the interfemoral membrane, and 

 by the very narrow wings. The small species of Tadarida are 

 the most rapid flyers of all the North American Bats, rowing 

 through the air with rapid wing beats and rather suggestive 

 of Swifts in their mode of flight. These Bats are firm and 

 compact in build, with heavier bodies than the same-sized 

 Bats of the family Vespertilionidae and appear to be more 

 highly specialized as aerial projectiles. The flight, while 

 broken by abrupt changes of direction, may be quite direct for 

 intervals of many yards. 



These Ba'ts are "house" Bats, colonies of many hundreds 

 sometimes taking up abodes in buildings where darkened nooks 

 are accessible. In San Antonio, Texas, municipal bat roosts 

 have been erected to encourage Tadarida mexicana and large 

 colonies have established themselves there. The purpose of 

 attracting these Bats was to bring in an enemy of the mos- 



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