THE ANIMAL LADDER. OF 
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Fic. 7.—1. The Animal Ladder of Life, showing the gradual development of ocean life to Amphibians, * 
reptiles, birds, and mammals (Children’s Encyclopedia). When the creatures of the ocean began to 
take to land habits, it seems they divided into two great branches. One branch evolved the Mammals 
such as the Kangaroos, Antelopes, and Apes. Mammals are creatures which are warm-blooded 
and suckle their young. The other branch evolved on from Amphibians to Crocodiles, Turtles, 
Lizards, Snakes, and lastly birds. af 
2. This is acommon South African Lizard, which has lost its legs. It has two tiny rudimentary front legs. 
The back legs have vanished. On dissection, the pelvis only isfound. This lizard is in the inter- 
mediary stage of development between a lizard and asnake. There is another common South 
African Lizard (Acontias meleagris), which burrows in the ground. It has lost all vestiges of legs, but 
has a rudimentary pelvis, shoulder girdle, and movable eyelids, so it is still called a Lizard. 
