peculiar clicking sound, which, as it is frequently emitted when the mouth is wide open, is probably produced in the throat. The Marmoset Monkey (Jacchus) we have heard utter a similar sound.
One large division of the Family have an extraordinary development of the skin of the face, sometimes taking the form of a leaf or an arrowhead, standing up from the nose; at others assuming an appearance too complicated for description. The ears, also, are, in general, large, and in many species, the tragus is so lengthened as to seem a second ear. The membranes of the ears, in some cases, meet above the head, and in others are produced, with strange convolutions, along the cheek
HEADS OF BATS;
Rhinolophus ferrum-equinum, and Megaderma frons.
to the muzzle. These expansions of naked and sensitive skin, in addition to the volar membrane, no doubt increase the peculiar capacity which the