426 BATS. 



All the teeth of the lower jaw touch each other ; in the upper 

 jaw the incisors are separated by a wide interspace from the canine. 



The dentition of the Long-eared Bat (Plecotus auritus) differs 

 from the foregoing chiefly by the absence of one of the small pre- 

 molars on each side of the upper jaw. In the Horse-shoe Bats 

 {Rhinolophus, PI. 112, fig. 5), the Barbastelles {Barhastellus) , the 

 Noctule {Vespertilio Noctula, PL 112, fig, 2), and the Pipistrelle 

 {Vespertilio pipistrellus) , the small premolars reduced to one on 

 each side of both jaws, are extremely minute, and seldom visible 

 from without. In the Serotine (Vespertilio serotinus, PI. 112, fig. 3) 

 the rudimental premolar is entirely wanting in the upper jaw, but 

 remains in the lower; and this condition of the molar series also 

 characterises the genera Rhinopoma, Noctilio, and many species 

 of Molossus and Nycticeus. In the genus Nycteris (PI. 112, fig. 

 6 and 7) the small premolars are absent in both jaws ; and the molar 

 series is reduced to the large premolar and three true molars, which are 

 present on both sides of both jaws, in all the foregoing Bats. 



The Bats with ciliated tongues, {Glossophaga, PI. 112, fig. 4, 4'), 

 have three premolars and three true molars on each side of both 

 jaws, rather small and slender canines, and two minute incisors on 

 each side of both jaws. 



The following are examples of the variation in the number of 

 incisive teeth : l^ in Taphozous perforatus, Geoff, and the species of 

 Megaderma : ^} in Molossus and Myoptera : l^ in Nyctinoma, Rhino- 

 poma, Rhinolophus and Dysopus : jEts in Vespertilio lasiurus and V. 

 paradoxus : fEf in Noctilio : ^Ef in Phyllostoma, Glossophaga and 

 Mormoops : g^f in Plecotus, Nycteris (PI. 112, fig. 6'^), and in most 

 species of the genus Vespertilio, as restricted by modern Naturalists. 



The molar teeth have a more trenchant character and 

 fewer points in the Leaf-nosed Bats (Phyllostoma) of South 

 America, which are commonly called Vampyres ; their canines 

 also, which are remarkably long and strong, sharp-pointed and 

 vertical in position, indicate a higher kind of animal diet than 

 that of the ordinary insectivorous Bats. The premolar teeth 

 are better developed than usual ; in the Phyllostoma hastatum 

 the first upper premolar has a strong, thick pointed crown, 



