The inner margin of the nostrils projects, a preparation for the tubular nostrils of Harpyia. The tail is absent. The premolars are three and the molars two. The pyloric region of the stomach is extended and twisted upon itself. Of this genus there are nearly sixty species, extending from Madagascar to Queensland. Thirty species inhabit the Australian, twenty the Oriental region. Madagascar has seven, and one species just enters the Palaearctic. The occurrence of this genus in India and in Madagascar is one of those facts which favour the view supported, on these and other grounds, by Dr. Dobson and Dr. Blanford that a connexion between India and Madagascar must once have existed; for these slow-flying creatures could hardly be believed capable of traversing vast stretches of ocean by their unaided efforts.[[384]]
Fig. 257.—Flying Fox. Pteropus poliocephalus. × ⅓.
Pteropus is represented in the Ethiopian region by the allied genus Epomophorus. Of this there are perhaps a dozen species. The teeth are reduced to two premolars in the upper jaw,
three remaining below; while there is but one molar in each upper jaw, and two in each lower. Dr. Dobson has studied the structure of the remarkable pharyngeal sacs which exist in the neck of the male, and are capable of inflation.
Pteralopex of the Solomon Islands has shorter ears than have many Pteropus, otherwise its external characters are the same. As in Pteropus nicobaricus, this genus has the orbits shut off by a bony ring, an extremely rare phenomenon in Bats. The canines have two cusps. The characters of the grinding teeth have already been mentioned. It is uncertain whether the only species of this genus, P. atrata, is, or is not, a vegetable feeder. Harpyia has shortish ears and extraordinarily prolonged and tubular nostrils. There is a hint of the accessory cusp to the canines mentioned above in Pteralopex. The incisors are reduced to one on each upper jaw, and none below. Cynopterus has also often bituberculate canines. It is an Oriental genus with several species.
Nesonycteris, with one species from the Solomon Islands, N. woodfordi, has the dental formula I 2/1 C 1/1 Pm 3/3 M 2/3. The index finger has no claw; the tail is absent. The premaxillae are separated anteriorly.
Eonycteris, with a single cave-dwelling species from Burmah, E. spelaea, has also no claw upon the index; the tooth formula is fuller by reason of the presence of an additional incisor below. The tongue is very long and is armed with papillae. There is a short but distinct tail.
Notopteris, from New Guinea and the Fiji Islands, is distinguished from the related genera by its long tail.
The remaining genera of Fruit Bats are Boneia, Harpyionycteris, Cephalotes, Callinycteris, and Macroglossus, from the Oriental region, and Scotonycteris, Liponyx, and Megaloglossus from the Ethiopian region; finally, there is the Australian Melonycteris.