660 CHIROPTERA 



surface of the muzzle, near its extremity) to the low band connect- 

 ing the bases of the large ears ; the sides of this depression being 

 margined as far back as the eyes by small horizontal cutaneous 

 appendages. All the species resemble one another closely, and are 

 mainly distinguished by the form of the tragus and the size and 

 relative position of the second lower premolar. With the exception 

 of N. jttvanica, they are all limited to the Ethiopian region. 



Family VESPERTILIONID^E. 



Nostrils opening by simple crescentic or circular apertures at 

 the extremity of the muzzle, not surrounded by distinct foliaceous 

 cutaneous appendages ; premaxillse small, lateral, and separated by 

 a wide space in front ; tragus distinct. In addition to these char- 

 acters, it may be observed that the skull is of moderate size, the 

 nasal and frontal bones not being much extended laterally or vertic- 

 ally, nor furrowed by deep depressions. The number of incisors 

 varies from to |, rarely (in Antrozmis only) \, premolars f, or f , 

 or |, rarely (in Vesperugo noctivagans of North America) f ; the 

 upper incisors are small, separated by a wide space in the middle 

 line, and placed in pairs or singly near the canine ; the molars are 

 well-developed, with acute W-shaped cusps. 



This family, which may be regarded as occupying a central 

 position in the suborder, includes the common simple-faced Bats of 

 all countries, of which the well-known Pipistrelle and the Whiskered 

 Bat (Vespertilio mystacinus) may be taken as familiar types, and its 

 species number more than 150, or considerably more than one-third 

 the total number of the known species of the entire order. The 

 various genera may be conveniently grouped into the Plecotine, 

 F'espertilionine, Miniopterine, and Thyropterine divisions. 



In the Plecotine division, of which the common Long-eared Bat 

 (Plecotus auritus) is the type, the crown of the head is but slightly 

 raised above the face-line, the outermost upper incisor is close to 

 the canine, and the nostrils are margined behind by grooves on the 

 upper surface of the muzzle, or by rudimentary nose-leaves ; the 

 ears also are generally very large and united. 



Plecotus. 1 Dentition : i % , c ^, p , m f ; total 36. Outer 

 margin of ear-conch ending abruptly near the angle of the mouth, 

 the inner margin with a more or less prominent rounded projection 

 directed inwardly above the base ; tragus very large, tapering up- 

 wards, with a lobe at the base of its outer margin, rounded, and 

 placed half horizontally. This genus is represented by the Euro- 

 pean Long-eared Bat (P. auritus), and P. macrotis, restricted to 

 North America. The latter is distinguished by the great size of 



1 Geoffroy, Descript. de VEgypte, vol. ii. p. 112 (1812). 



