144 



LIVING CREATURES. 



the ground ! Here the toads and frogs pass through 

 some wonderful changes from the egg to the complete 

 form. These changes are easily seen and watched in 

 the aquarium. 



The eggs, or spawn, are laid in a kind of jelly, which 

 fastens them to a stick or plant in or very near the 

 water (i). After about a month the eggs hatch, when 



Fig. 12. Eggs, Tadpoles, and Frogs. 



there appear very small tadpoles, with head and tail, 

 and a pair of holders behind the mouth (2). Outside 

 gills grow, and become large, like plumes (3). You 

 remember for what purpose are gills in the clam and 

 oyster. Then the gills disappear (4 back view 5). 

 Hind legs put forth (6). Fore legs follow (7). As the 

 legs grow, the tail shrinks away (8). The tail goes, 

 and the perfect little frog comes (9). 



All this time changes have been going on within the 

 tadpole. When the outside gills passed away, inside 



