PIPA, a genus of batrachians, in general form resembling frogs and toads, and char acterized by the very broad and triangular head, the sides of which are destitute of the glands (pa•otoids) so large in the true toads; the eyes small, and situated near the margin of the lower jaw; the ear concealed beneath the skin; the tongue merely rudimentnry; the jaws destitute of teeth; the fore-feet not webbed, but divided into four fingers, each of which divides at the extremity into four small points, these again being minutely divided in a similar manner; the hind-feet five-toed and completely webbed; the larynx of the male extremely large—a triangular bony box, within which are two small movable bones for occasionally closing the entrance of the bronchi; the back of the female fur nished with numerous cells or pouches, in which the eggs are hatched, and the young undergo all their transformations till they have attained a form similar to that of their parents. These characters are so remarkable as to make the creatures of this genus objects of peculiar interest; but particularly the mode of rearing the young. It was at
first supposed that the young were produced in some unusual way in the cells from which they were seen finally to emerge; but this is not the case. The eggs are deposited by the female in the ordinarrmanner, and are carefully placed by the male in the cells of her back, which close over them. When the young are ready to use their limbs they struggle out of the cells, to which they never afterwards return. The best-known species of pipa is that commonly called the Surinam toad (P. surinamensis), a native of Guiana and other warm parts of continental America,- where it inhabits swamps and ditchefi, and is occasionally found in damp and dirty corners of houses. It is sometimes 7 in. long; its color is brownish-olive above, whitish below; the skin covered with small hard granules, mingled with occasional horny tubercles. The whole aspect of the creature is peculiarly hideous.