44 



NORTH AMERICAN FAUNA 66 



Figure 15. — Distribution of Myotis keenii septentrionalis. 



Measurements. — External measurements of three adults from 

 Plummers Island, Montgomery County, are as follows: Total len^h 

 81, 87, 75; tail vertebrae 38, 35, 35; hind foot 9, 9, 10. Some cranial 

 mmsurements of four adults from Plummers Island are: Greatest 

 length 14.5 (14.4-14.7) ; zygomatic breadth 8.9 (8.8-9.0) ; interor- 

 bital breadth 3.6 (3.6-3.7) ; length of maxillary toothrow 5.9 (5.7-6.0). 



Habitat and habits. — This species roosts in small colonies in caves, 

 and under loose bark on trees. Frequently it is found in association 

 with the little brown myotis, from which it differs little in habitat 

 selection or habits, except that it seems to be more solitary. Mansueti 

 (1941, pp. 56-57) found one sleeping under the bark of a dead stand- 

 ing tree near Arbutus, Baltimore County. When he peeled the bark 

 away, the bat flew to a nearby tree and crawled up under some loose 

 bark on it. This species is more abundant than the few Maryland 

 records indicate. 



Specimens examined. — Baltimore County: Bare Hills, 1. Mont- 

 gomery County: Cabin John Bridge, 1; Plummers Island, 5. Prince 

 Georges County: Muirkirk, 1. District of Columbia: 4. 



Other records and reports. — Baltimore County: Arbutus (Man- 

 sueti, 1941); Lake Roland (Bures, 1948: 63). Montgomery County: 

 Forest Glen (Miller, 1897: 76). Washington County: Round Top 

 Mountain, near Hancock (bat banding record, U.S. Fish and Wildlife 

 Service) . 



