272 



ANIMAL STUDIES 



half of the body longer than wide. The crah in the megalops 

 stage looks very much like a tiny lobster or shrimp. The 

 tail soon disappears and the body widens, and the final stage 

 is reached. 



Interesting examples of metamorphosis occur in nearly 

 all species of the animal kingdom, those mentioned being, 



FIG. 151. Metamorphosis of the crab, a, the zoe'a stage ; b, the megalops ; 

 c, the adult. 



perhaps, the most conspicuous. In many families of fishes 

 the changes which take place in the course of the life cycle 

 are almost as great as in the case of the insect or the toad. In 

 the lady-fish (Albula vulpes) the very young are ribbon-like in 

 form, with small heads and very loose texture of the tissues, 

 the body substance being jelly-like and transparent. As the 

 fish grows older the body becomes more compact, and there- 

 fore shorter and slimmer. After shrinking to the texture of 

 an ordinary fish, its growth in size begins normally, although 



