. Advanced biology. Biology; Physiology; Reproduction. LIFE HISTORY OF THE FROG 287 Life history of the frog. The little tadpole then hatches from the gelatinous egg. For the first two or three days, it remains attached to grass by a sucker-like mouth. Then it begins to feed on algae and other vegetable matter. When first hatched, it has ternal gills, which grow out into long, branching tufts. Later, four pairs of internal gills are formed and the ex- ternal gills are ab- sorbed. The hind limbs soon appear; later, the fore limbs develop. The tail then decreases in size and is gradually ab
. Advanced biology. Biology; Physiology; Reproduction. LIFE HISTORY OF THE FROG 287 Life history of the frog. The little tadpole then hatches from the gelatinous egg. For the first two or three days, it remains attached to grass by a sucker-like mouth. Then it begins to feed on algae and other vegetable matter. When first hatched, it has ternal gills, which grow out into long, branching tufts. Later, four pairs of internal gills are formed and the ex- ternal gills are ab- sorbed. The hind limbs soon appear; later, the fore limbs develop. The tail then decreases in size and is gradually ab- sorbed. The gills, too, are absorbed, and lungs are formed to take their place. The two-chambered heart of the tadpole becomes the three-chambered heart of the frog. Finally the form resembling that of the adult frog is acquired. Reproduction of other animals. The reproduction of all higher animals is similar to the reproduction of the frog. All females have ovaries producing eggs, and males have spermaries or testes producing sperms. The sperms fertilize the eggs and thereby. N. Y. Zoological Hoc. The frog first hatches from the egg in the form of a tadpole. Gradual changes take place which transform it into the adult frog. This change of body form is called Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original Wheat, Frank Merrill; Fitzpatrick, Elizabeth T. New York ; Boston [etc. ] : American Book Company
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Keywords: ., bookcentury1900, bookdecade1920, booksubje, booksubjectphysiology
