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the air. If one should use a narrow and deep vessel like a fruit jar, 

 only a small amount of air could be taken up by the water and the 

 tadpoles would be half suffocated. 



As the tadpoles grow older their lungs develop more and more and 

 they go oftener to the surface to get the air directly from the limitless 

 supply above the water. They are getting used to breathing as they 

 will have to when they live wholly in the air. 



Disappearance of the tail. — From the first to the middle of June the 

 . tadpoles should be watched with especial care, for wonderful things 

 are happening. Both the fore and hind legs will appear, if they have 

 not already. The head will change in form and so will the body; 

 the color will become much lighter, and, but for the tail, the tadpole 

 will begin to look quite like its mother. 



If you keep an especially sharp lookout do you think you will see 

 the tail drop off ? No, toad nature is too economical for that. The 

 tail will not drop off, but it will be seen to get shorter and shorter 

 every day ; it is not dropping off but is being carried into the tadpole. 

 The tail is perfect at every stage; it simply disappears. How does 

 this happen ? This is another thing that it took scientific men a long 

 time to find out. It is now known that within the body there are 

 many living particles that wander about as if to see that everything is 

 in order. They are called wandering cells, w^hite blood corpuscles, 

 phagocytes and several other names. These wander into the tail at 

 the right time and take it up particle by particle. The wandering 

 cells carry the particles of tail into the body of the tadpole where they 

 can be made use of as any other good food would be. This taking in 

 of the tail is done so carefully that the skin is never broken, but covers 

 up the outside perfectly all the time. Is not this a better way to get 

 rid of a tail than to cut it off ? 



Beginning of the life on the land. — Now when the legs are grown 

 out, and the tail is getting shorter, the little tadpole likes to put its 

 nose out of the water into the air; and sometimes it crawls halfway 

 out. When the tail gets quite short, often a mere stub, it will crawl 

 out entirely and stay for some time in the air. It now looks really 

 like a toad except that it is nearly smooth instead of being warty like 

 its mother, and is only about as large as the end of one's httle linger. 



Finally the time comes when the tadpole, now transformed into a 

 toad, must leave the water for the land. 



