refreshing shower, which had just before fallen, to go out either in pursuit of food or of a more convenient habitation*.

Frogs are numerous in the parts of America about Hudson's Bay as far north as latitude 61°. They frequent there the margins of lakes, ponds, rivers, and swamps; and as the winter approaches, they burrow under the moss, at a considerable distance from the water, where they remain in a frozen state till spring. Mr. Hearne says he has frequently seen them dug up with the moss frozen as hard as ice. In this state their legs are as easily broken off as the stem of a tobacco pipe, without giving them the least sensation : but by wrapping them up in warm skins, and exposing them to a slow fire, they soon come to life, and the mutilated animals gain their usual activity: if, however, they are permitted to freeze again, they are past all recovery †.

The mode of respiration in these animals, in common with many of the other reptiles, is exceedingly curious. The organs adapted to this use are not placed in the belly, nor in the lungs themselves, but in the mouth. Behind the root of the tongue is the slit-like opening of the trachea and at the front of the upper part of the head are two nostrils, through which the animal always draws the air, never opening its mouth for this purpose. Indeed the jaws during this action are kept closely locked into each other by grooves; for if the mouth is kept open it can

* Ray's Wonders of the Creation, 165.

+ Hearne, 397.

not respire at all, and the animal will presently be seen struggling for breath. When we observe it carefully, we perceive a frequent dilatation and contraction in the skinny bag-like part of the mouth which covers the under jaw. From this it would appear at first sight, as if the creature lived all the while on one mouthful of air, which it seems to be playing backwards and forwards betwixt its mouth and lungs. But for each movement in the jaw a corresponding twirling movement may be observed in the nostrils. The mouth seems therefore to form a sort of bellows, of which the nostrils are the air-holes, and the muscles of the jaws by their contraction and relaxation make the draught. The nostrils are so situated that the least motion on them enables them to perform the office of a valve. By the twirl of the nostril the air is let into the mouth, when a dilatation of the bag takes place it is then emptied from the mouth, through the slit behind the tongue, into the lungs,. when there is a slight motion in the sides of the animal, and the muscles of the abdomen again expel it ; and soon afterwards a second twirl in the nostrils. takes place, and the like motions follow. Thus it appears that the lungs are filled by the working of the jaws, or, in other words, that Frogs swallow air much in the same manner that we swallow food.

Frogs cast their skins at certain periods.-They arrive at full age in about five years, and are supposed to live to twelve or fifteen.-Their voice is hoarse and unpleasant. They are so tenacious of life as to survive even the loss of their head for several hours.

This species is not so much in request for food as

9

the following, not being so white, nor altogether so palatable. The hind-legs, however, are eaten, and the fore-legs and livers often form an ingredient in the continental soups.

THE EDIBLE FROG*.

The Edible Frog is considerably larger than the common species, and, though somewhat rare in England, is found in plenty in Italy, France, and Ger

many.

Its colour is an olive green, distinctly marked with black patches on the back, and on its limbs with transverse bars of the same. From the tip of the nose, three distinct stripes of pale yellow extend to the extremity of the body, the middle one slightly depressed, and the lateral ones considerably elevated. The under parts are of a pale whitish colour tinged with green, and marked with irregular brown spots.

The spawn of the present species is not often deposited before the month of June. During this season the male is said to croak so loud as to be heard to a great distance. In some particular places where these animals are numerous, their croaking is very oppressive to persons unaccustomed to it.

The globules of spawn are smaller than those of the Common Frog, and the young are considerably

* SYNONYMS.-Rana esculenta. Linn.--Esculent Frog, Green Frog. Shaw.-Edible Frog. Penn. Shaw's Gen. Zool. vol. 3. tab. 31.

longer in attaining their complete state, this seldom taking place till November. They arrive at their full growth in about four years, and live to the age of sixteen or seventeen.-They are excessively voracious, frequently seizing young birds, and even mice, which like the rest of their prey of snails, worms, &c. they swallow whole*.

These poor creatures are brought from the country, thirty or forty thousand at a time, to Vienna, and sold to the great dealers, who have conservatories for them, which are large holes, four or five feet deep, dug in the ground, the mouth covered with a board, and in severe weather with straw. In these conservatories, even during a hard frost, the frogs never be come quite torpid. When taken out and placed on their backs, they are always sensible of the change, and have strength enough to turn themselves. They get together in heaps, one upon another, instinctively, and thereby prevent the evaporation of their humidity; for no water is ever put to them. In Vienna, in the year 1793, there were only three great dealers; by whom most of those persons were supplied who brought them to the market ready for the cookt.

From their spawning-time being very late, it is supposed that those animals that are brought to market before the month of June for the Edible Frog, are either Common Frogs, or sometimes that they are even Toads..

* Shaw's Gen. Zool. iii. 103.

+ Townson's Travels, 14.

THE BULL FROG *.

This is an animal that frequently measures from the nose to the hind-feet a foot and a half, or upwards. The colour of its body is a dusky olive or brown, marked with numerous dark spots, lighter beneath than above. The external membranes of the ears are large, round, and of a brownish red, surrounded by a yellowish margin.

The interior parts of America are the principal residence of this species, where, at the springs or small rills, they are said to sit in pairs. In Virginia they are in such abundance, that there is scarcely a single spring that has not a pair of them. When suddenly surprised, by a long leap or two they enter the hole, at the bottom of which they lie perfectly secure. The inhabitants fancy that they purify the water, and respect them as genii of the fountains. -Kalm informs us that they frequent only ponds and marshes.

Their croaking is said somewhat to resemble the hoarse lowing of a bull; and when, in a calan night, many of them are making a noise together, they may be heard to the distance of a mile and a half. The night is the time when they croak, and they are said to do it at intervals. In

*SYNONYMS.-Rana Catesbeiana. Shaw.-Rana ocellata. Linn.??-Bull Frog. Catesby. Shaw's Gen. Zool. vol. 3. tab. 33. Dr. Shaw is of opinion that Linnæus has described the Argus Frog of General Zoology under the name of Rana ocellata. + Catesby, ii. 72,