TADPOLES AND FROGS 211 



is much more rapid in Italy and the South of France 

 than in England. At first they are so small that it is 

 difficult to distinguish, except with a pocket-lens, the 

 little black plume-like gills on each side of the head, 

 and it is only as they grow bigger and lose these little 

 plumes that the young things assume the characteristic 

 shape of a rounded head really head and body with 

 a long flattened tail which strikes vigorously to the right 

 and left, and enables the tadpole to swim like a fish. 



I suppose that every one, or nearly every one, knows 

 that these swarming little black tadpoles are the young 

 of frogs and toads. As the season goes on they grow 

 to as much as an inch and a quarter (sometimes an inch 

 and three-quarters) in length, and develop a number of 

 golden metallic-looking spots in the skin, which give 

 them a brownish hue. Both the fore and the hind 

 limbs have now developed, but are hidden beneath the 

 skin, and all this time the tadpole is breathing, like a 

 fish, by means of gills, concealed from view by a fold of 

 skin. Very early it acquires a pair of lungs, and by the 

 time the legs break through the skin (the hind legs do 

 so first) the lungs are inflated, and help in respiration. 

 Now the head becomes modelled like that of a young 

 frog, the tail ceases to grow, its flat transparent border is 

 absorbed and eaten by " phagocytes," and the legs 

 become strong and large. Soon the gills atrophy, and 

 the young creature crawls out of the water and spends 

 much of its time in the damp grass and herbage near its 

 native pond, rapidly assuming the shape of a frog. An 

 interesting fact is that all the time that it is a tadpole 

 the little animal eats vegetable food or soft animal food 

 (even other tadpoles), has horny lips, and a very long 

 intestine, coiled like a watch-spring. But as soon as it 

 leaves the water it becomes purely carnivorous, feeding 

 on small insects and worms, and its intestine straightens 



