10 



THE FROG 



CHAP. 



in the water. After a while the gills begin to shrivel up 

 (3, 4), and the tadpole then comes periodically to the 

 surface to breathe, lungs having in the meantime made 



FIG. i. Stages in the life-history of a Frog, from the newly-hatched tadpoles (i) to 

 the young frog (8). Natural size. 20, is a magnified view of 2. (After Mivart.) 



their appearance. A pair of little hind-limbs appears at 

 the root of the tail, and a pair of fore-limbs behind 

 the head (5, 6). As these increase in size the tail slowly 

 dwindles, the head and trunk assume the characteristic 

 frog-form, and the animal now comes on land and hops 



