24 VERTEBRATES I MAMMALS. 



and pointed nails. They are nocturnal in their habits, 

 and during the day remain in caves, hollow trees, or 

 other dark places, suspended by their hooks, or by the 

 nails of their hind feet. In cold and temperate regions 

 they pass the winter in a state of lethargy. Although 

 their eyes are so small, their large ears and broad wings 

 possess such a delicate sensibility that bats are enabled 

 to fly unharmed through the most winding and compli- 

 cated passages, and that, too, after their eyes have been 

 destroyed. Bats may be divided into two great groups. 



1. Frugivorous Bats, or Rousettes, have trenchant in- 

 cisors in each jaw, grinders with flat crowns, and feed 

 chiefly upon fruit, but also capture birds and small quad- 

 rupeds. About forty species are known, inhabiting 

 mainly the East Indies and tropical Africa. They are 

 the largest of the bats, and the flesh of some is used for 

 food. The Genus Pteropus is the principal one. 



The Black Rousette, P. edulis, Geoff., of the Straits 

 of Sunda and the Moluccas, is of a blackish-brown color, 

 and measures nearly four feet between the extremities of 

 the wings. Its loud cry resembles that of the goose. 



2. Insectivorous Bats have three grinders on each side 

 in each jaw, bristled with conical points, that are preceded 

 by a variable number of false molars. About two hun- 

 dred species are known. 



The Genus PJiyllostoma Vampires is characterized 

 by a membrane in the form of a leaf, which is reflected 

 crosswise on the end of the nose. They belong wholly 

 to tropical America, and have the reputation of inflicting 

 severe wounds upon men and animals, which they bite in 

 order to suck their blood. 



The Vampire Bat, P. spectrum, Linn., is of the size 

 of a magpie, reddish brown, and has the leaf in the form 

 of a funnel. 



The Genus Vespcrtilio Common Bats has the muz- 



