Alligatoridae 

 (Alligator) 



Fossil Labyrinthodontia 

 (Labyrinthodonts) 



Chelidae 

 (Snake-necked turtle) 



Figure 274. Some orders and families of reptiles. The lines indicate probable relationships. 

 (Based on a diagram by Charles M. Bogert, Curator of Amphibians and Reptiles, American 

 Museum of Natural History; made expressly for this book.) 



407 



