REPRODUCTION AND LIFE HISTORY 



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as a " tadpole" or "polliwog." At first it is attached to some 

 water weed by means of a suckerlike projection ; but in one or 

 two weeks' time, depending upon temperature, it frees itself 

 and becomes a free-swimming tadpole. A mouth is formed at 

 the suckerlike projection, and the tadpole begins to feed upon 

 algae and other tiny water plants. At this time, gills are present 

 on the outside of the body. Later, these gills are replaced by 

 others which grow out under the fold of the skin. Water reaches 

 the gills through the mouth and passes out through a hole on the 

 left side of the body. As the tadpole grows larger, legs appear. 

 The hind legs grow out first. At the same time the tail becomes 

 shorter and shorter. Shortly after the legs appear, the gills are 

 absorbed, and lungs take their place. At this time the young 

 animal may be seen coming to the surface of the water for air. 



tadcpotes e w attached: to aleaf- 



Traae the life history of the frog. How long does it take for the frog to pass through 

 this metamorphosis ? (Use the frog co.n:non to your locality to answer this question. ) 



Changes in the diet of the animal also occur ; the long, coiled 

 intestine is transformed into a much shorter one. The animal. 



