with which we are most familiar, but some foreign species utter various other discordant noises, such as shrieks long-protracted, and intolerably shrill and piercing, whistlings, snorings as of a person in oppressed slumber, or the deep bellowings of a bull.
In temperate countries they become torpid during winter, retiring on the approach of cold weather into the mud at the bottom of ponds, where multitudes huddle together in numerous assemblages. The mild air of spring awakens them from their death-like sleep, when they separate, emerge from their retreat, and soon make the shores of our waters vocal, if not musical, with the pertinacity of their sexual call.
Genus Rana. (Linn.)
The skin in this, the typical genus, is smooth; the hinder legs are very long, muscular, and formed for leaping; the toes of the hind feet are connected by a web; there are teeth on the upper jaw, and on the palate; the gape is very wide; the tongue, broad, soft, notched at the extremity, is folded back, the anterior portion lying ordinarily on the posterior; the eyes are brilliant and prominent, and elevated above the forehead.
The Common Frog (Rana temporaria, Linn.) is familiar to every child. Every rivulet and river, every lake, pond, and pool, every stagnant or running ditch by the road-side, and even the little collections of rain-water that lie in the gravel-pits of the common, are pretty sure to be tenanted by this vigorous and graceful swimmer, or by its black and wriggling tadpoles. When full grown the Frog is rather more than
