Hatching and Progress of the Young Frogs. 



Figure I represents the embryo as it appears several days after 

 the egg is deposited. Figure 2 gives an outline of its form ; the 

 arrows at the side of the head shows the currents of water, which 

 are seen to flow to the branchiae by the breathing of the young 

 animal. A short period brings it to the form represented in Nos. 

 3 and 4, the latter representing the head. Figure 5 shows the form 

 of the tadpole when first hatched, which usually takes place about 

 four weeks after the depositing of .the egg. Figures 6, 7 and 8 

 shows various stages of its development ; the latter representing the 

 tadpole, called pollywog sometimes ; this, for some time, now under- 

 goes little change of form, but increases in size. At length the 



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