TYPICAL BATS. 41 



escape. Every portion of such insects, including even the 

 wings, is consumed. 



GENUS VESPERTILIO. 

 Vespertilio, Linn., Syst. Nat. ed. 12 vol. i. p. 47 (1766). 



This genus, in which are included the whole of the six re- 

 maining British Bats, may be at once distinguished from Ves- 

 perugo by the presence of three pairs of pre-molar teeth in the 

 upper jaw, the number of teeth on each side behind the canine 

 being thus six, in place of five or four. Together with certain 

 allied genera, it is further distinguished from Vesperugo and 

 its allies by the outer margin of the conch of the ear com- 

 mencing abruptly nearly opposite the inner margin of the ear- 

 let, or tragus, instead of near the angle of the mouth. The 

 thin and narrow ears are also, generally at least, as long as the 

 head, instead of being triangular or rhomboidal, and shorter 

 than the latter ; while the long and narrow tragus, if curved at 

 all, is inclined outwards instead of inwards. Then, again, the 

 muzzle is narrow and hairy in front, instead of being nearly 

 naked, with lateral glandular swellings. From its nearest 

 allies of the same group, Vespertilio is distinguished by the 

 simple and scarcely projecting nostrils, the aperture of which 

 is crescentic, as well as by the small size of the two an- 

 terior pre-molar teeth, as compared with the last tooth of the 

 same series. 



Although containing fewer species than the last, the present 

 genus has a wider geographical distribution than any other in 

 the entire Order, its range including the whole of the temper- 

 ate and tropical regions of both hemispheres. From their 

 close similarity to one another, the majority of the species are 

 exceedingly difficult to distinguish. The Old World species 

 may, however, be thrown into two groups, or sub-genera, 

 according as to whether the feet are relatively large or of 



