50 



NORTH AMERICAN FAUNA 66 



General distribution. — From central Minnesota and southern Quebec south into 

 Georgia and western Florida ; west to Oklahoma, Texas, and Tamaulipas. The 

 center of its abundance is the Ohio River Valley ; north of this it occurs locally 

 in summer (Davis and Mumford, 1962, p. 396). 



Distribution in M aryland. — Probably ranges throughout all sections 

 of the State, although there are no records of it from the Eastern Shore 

 section. 



Distinguishing characteristics. — Teeth 2/3, 1/1, 2/2, 3/3, = 34; 

 smallest bat in Maryland; coloration of dorsum grayish to reddish- 

 bro^vn, each hair tricolored, plumbeous at base, dark brown at tip, 

 with central portion yellomsh-brown; flight weak and erratic, giving 

 the animal somewhat the appearance of a large fluttering moth. 



Measurements. — External measurements of 11 adults from Washing- 

 ton, D.C., are as follows : Total length 81.6 (75-90) ; tail 39.5 (37-42) ; 

 hind foot 8.5 (8.0-9.0). Some cranial measurements of 10 adults from 

 Washington are as follows: Greatest length 12.8 (12.4-13.1) ; zygo- 

 matic breadth 7.9 (7.7-8.2) ; interorbital breadth 3.5 (3.4-3.6) ; length 

 of maxillary toothrow 4.3 (4.2-4.4) . 



Habitat and habits. — This is a wide-ranging species that hibernates 

 in caves, mine shafts, and rock crevices. During the summer months it 

 probably spends the daylight hours in trees, although it is sometimes 

 found in buildings. It is most frequently encountered in wooded areas 

 near water. The pipistrelle is believed to have a feeding range of at 

 least 5 or 6 miles, and a homing instinct has been demonstrated by 

 tracing banded bats for distances up to 80 miles. Individuals roost 

 year after year in the same cave. 



Mating occurs in November, and young are born the last part of J une 

 or early July. Usually two constitute a litter, but there are occasionally 

 triplets, and sometimes only a single offspring. By the time they are 

 about a month old they are able to fly, and shortly thereafter begin to 

 shift for themselves. Since pipistrelles are so small their food is proba- 

 bly restricted to insects such as flies, moths, and the smaller bugs and 

 beetles. 



Despite their diminutive size, pipistrelles apparently have a long 

 life span. Banded individuals have been recovered in good health as 

 long as 10 years after they were originally tagged. 



Specimens examined. — Anne Arundel County: Magatha R. (= Ma- 

 gothy River?) , 2. Charles County: Marshall Hall, 13. Garrett County: 

 Near Oakland, 1. Montgomery County: Capitol View, 1 ; Glen Echo, 1 ; 

 Great Falls, 1; Plummers Island, 2. Prince Georges County: Hyatts- 

 ville, 1; Laurel, 1; near D. C. line, 6. St. Marys County: St. George 

 Island, 4; District of Columibia: 40. 



Other records and reports. — Baltimore County: Bare Hills (Bures, 

 1948: 64); Orange Grove (Hampe, 1939: 5). Washington County: 



