CALIFORNIA MASTIFF BAT 



quito. Dr. Charles A. R. Campbell of San Antonio has 

 written a book on municipal bat roosts and believes that they 

 are an asset, but Dr. E. W. Nelson, formerly Chief of the 

 U. S. Biological Survey, and other observers question the 

 value of Bats as a mosquito control. 



Genus Eumops 



Dentition: Incisors, ^; Canines, {; Premolars, f or §; Molars, 

 1=30 or 28. 



California Mastiff Bat. — Eumops californicus 



(Merriam) 



Names. — California Mastiff Bat; Bonnet Bat. 



General Description. — Largest of the Bats found in the 

 United States. Body large and robust, wings small and 

 narrow; ears very large, low, broad, and joined to one another 

 across forehead; a well-developed keel extending across ear to 

 form a broad shelf over eye; tragus small and fiat; ear mem- 

 branes tough and leathery; pelage short and velvety to the 

 touch; a thin strip of hair along upperside of forearm, mem- 

 branes otherwise naked; long hairs on toes. 



Color. — Sexes colored alike; no marked seasonal variation. 



Upperparts everywhere sooty brown, pelage lighter at 

 base; membranes brownish black; underparts only slightly 

 paler than upperparts. 



Measurements. — Total length, 6.5 inches; tail vertebrae, 2 

 inches; hind foot, .72 inch; forearm, 2.9 inches. 



Geographical Distribution. — Found in southern California 

 and Arizona east into southern Texas, in the Lower Sonoran 

 Zone; rather local in its distribution. 



Only the one species of Eumops is found as far north as the 

 United States; this genus is southern in its distribution. The 

 California Mastiff Bat is much the largest and strongest Bat 

 found in the United States and on the micre basis of size may 

 be readily identified. The large ears which overhang and 

 completely hide the head and face from above are another 

 infallible character. 



This Bat has been taken only at a few localities and appears 

 to be sporadic in distribution. Most of the specimens have 

 been found in or about buildings. 



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