Tadpole
the larva of the anurous amphibia, sometimes so far extended as to include larvæ of the urodela, which undergo a much less complete metamorphosis. At first the young have no respiratory organs or limbs. They are all head and tail with simple entire gills which soon disappear, to be followed by METAMORPHOSIS OF A FROG others of more complicated structure, situated within the cavity of the body as in fishes. After a certain length of time the hind legs begin to appear, the head becomes more developed, and the body TADPOLE assumes a more compact form. Still later the forelegs are found to exist fully formed beneath the skin and ready ultimately to burst forth. The tadpole at first seems to derive its subsistence from the fluid absorbed within its body and on the surface, but soon begins to seek its food amidst softened or decomposing vegetable matter. From that period the tadpole begins to assume more and more the appearance of a frog. Toes appear on its hind legs, the tail very rapidly disappears by absorption, and finally the forelegs become fully developed and the metamorphosis of the tadpole is completed.