Fish Salamander Tortoise Chick Pig Sheep Rabbit 



Fig. 139. Parallelism in development of backboned animals 



The three rows of embryos represent distinct stages of development. In the first row 

 the stages of the different species are very much alike; in each succeeding stage they 



are more distinctive 



Fig. 140. Metamorphosis in man 



A comparison of the infant and the adult shows that after birth the legs of the baby 



grow more than any other part, whereas the head grows the least. A study of this 



figure will show other changes that take place in the outward form 



