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ZOOLOGY 



Early during its transformation the tadpole loses its gills, these 

 being replaced by lungs. At this time the young animal may be 

 seen coming to the surface of the water after a bubble of air. 

 Changes in the diet of the animal also take place at this stage of 

 metamorphosis; the long coiled intestine is transformed into a 



Stages in the life of tadpoles of the green frog. The two large tadpoles are in their second 



summer. Photographed by Overton. 



much shorter one in the adult. The animal, now insectivorous in 

 its diet, becomes provided with tiny teeth and a mobile tongue, 

 instead of keeping the horny jaws used in scraping off alga3. After 

 the tail has been completely absorbed and the legs have become 

 full grown, there is no further structural change and the metamor- 

 phosis is said to be complete. 



