Page:Natural History, Reptiles.djvu/257

Rh dew or rain spread on the surface of the leaves is rapidly absorbed into the system, and reserved to supply the moisture needful for cutaneous respiration, as already explained. In the night, they are active and vociferous, and the woods in the tropics then resound with the various sounds emitted by these creatures. Some utter a pleasing chirp, or clear whistle, like the voice of a bird; others produce a ringing shriek, so loud and piercing as to be almost unbearable, while yet others supply the bass of this nocturnal concert, groaning and snoring in great variety of deep, hollow, guttural sounds. These noises reiterated with incessant pertinacity, through the livelong night, mingled with the shrill crinking of locusts and Cicadæ, quite banish sleep from a stranger’s eyes; but habit, as in other things, soon familiarises the ear to these discordant noises, and they cease to be perceived. These cries are uttered only by the males; which are furnished beneath the throat with a dilatable skin, capable of being inflated into a tense globose bladder, during the emission of the sound.

The prey of the Hyladæ consists of insects and similar small creatures, which are taken by the instantaneous projection of the tongue. Their upper jaw is furnished with teeth like that of the Frogs, but the manner in which they are arranged differs in different genera. The form of the tongue also varies; in some it is forked, in others it is heart-shaped, and in others it is long and ribbon-like. The toes are for the most part webbed, but in several genera they are free, and in one they are fringed with a free membrane