50 SAURIA. 



10. Their eggs have a cretaceous covering of greater or less firmness. 



11. The young animals undergo no metamorphosis. 



Remarks. Brogniart first established the order Sauria, and gave it accurate 

 and well defined hmits; before his time, Linnseus arranged in the genus Lacerta, 

 not only all Lizards, but Salamanders and Tritons also. This order at present 

 includes nearly five hundred species, distributed in eight families. Of this great 

 number only about fourteen different species have hitherto been found within the 

 limits of the United States. 



