The genus Vespertilio contains some forty-five species, and is world-wide in range. It has one more premolar in the upper jaw than has Vesperugo. There are no less than six British species, of which V. murinus is the largest species of Bat recorded from this country, but is not quite certainly indigenous.
Plecotus has very long ears. The dentition is I 2/3 C 1/1 Pm 2/3 M 3/3. The tragus is very large. There are but two or possibly three species, of which one is North American, and the other is the Long-eared Bat, P. auritus, of this country, but ranging as far as India. The shrill voice, inaudible to some ears, of this Bat has been heard of by everybody.
Synotus includes the British Barbastelle, S. barbastellus, as well as an Eastern form. It differs from the last genus principally by the loss of a lower premolar. The ears, too, are not so large. Otonycteris, Nyctophilus, and Antrozous are allied genera; the last is Californian, the others Old-World forms.
Kerivoula (or Cerivoula) has a long, pointed, narrow tragus. The tail is as long as or longer than the head and body. The dentition is as in Vespertilio; but the upper incisors are parallel instead of divergent as in that genus. The brilliantly-coloured K. picta is, on account of this very fact, the best-known species. The name Kerivoula, a corruption of the Cinghalese "Kehel vulha," signifies plantain bat. This Bat has been described as looking, when disturbed in the daytime, more like a huge butterfly than a Bat, which is naturally associated with sombre hues. Other species occur in the Oriental, Australian, and Ethiopian regions.
Miniopterus has a premolar less in the upper jaw; it has a long tail as in the last genus. One species, M. scheibersi, has almost the widest range of any Bat, it being found from South Europe to Africa, Asia, Madagascar, and Australia.
Natalus is an allied form from Tropical America and the West Indies. It is chiefly to be separated from Kerivoula by the short tragus to the ear.
Thyroptera is also South American. It is distinguished by the curious sucker-like discs upon the thumb and foot. These "resemble in miniature the sucking cups of cuttle-fishes." The Madagascar genus, Myxopoda, with but one species, has also an adhesive but horse-shoe-shaped pad upon the thumb and foot.
Scotophilus has shortish ears with a tapering tragus. The tail is shorter than the head and body, and is nearly contained within
