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THE AMERICAN NATURALIST [Vol. XLIII 



glands, however, and it is by their sticky secretion and not 

 by suction that the tadpole attaches itself to objects. 



For a day or two after hatching the tadpoles cling most 

 of the time to the gelatinous strings or near-by plants. 

 The tail is noticeably compressed on the second day and 



the larva makes excursions from time to time, eventually 

 reaching the shallow water. The mouth is formed in 

 three to seven days, and the larva? begin feeding. Hence- 

 forth the tadpole is a voracious feeder, living largely upon 

 the slime at the bottom of the pond and that collected upon 

 sticks and plants. Meats, fresh or putrid, are eagerly de- 

 voured and vegetable matter is also eaten. In this way 

 the tadpoles play the part of scavengers (Fig. 5). 



The first gills are external and are soon replaced "by- 

 internal ones. 



The first indication of transformation is the growth of 

 the legs. They appear as small knobs or buds about the 

 twentieth day of the tadpole's life. Both pairs grow rap- 

 idly and within ten days may be fully formed. The front 

 legs, concealed in the gill chamber, appear suddenly a 

 short time before the tadpole leaves the water. One is 

 thrust out at the breathing pore and the other breaks di- 

 rectly through the operculum. The tadpole is now almost 

 ready to abandon its aquatic life and within a day it may 



