SEA-SERPENTS 



191 



four and a half feet. This nearly perfect head was for a time a 

 stumbling- block to many naturalists, some of whom were of 



FIG. 67. Skull of Mosasaurus Hoffinanni. The original is 4 ft. by 2 ft. 



opinion that it belonged to a whale. Cuvier and others con- 

 sidered it to be a kind of link between 

 the Iguanas and the Monitors. 1 



The entire backbone of the Maestricht 

 animal appears to have consisted of one 

 hundred and thirty-one vertebras, of which 

 ninety-seven belonged to the tail. The 

 total length of the skeleton is estimated at 

 twenty-four feet, and the head was about 

 one-sixth of the total length. The tail is 

 only ten feet long, whereas in a crocodile 

 the tail exceeds the length of the body. FlG - 68.-Teeth of Mo- 



sasaurus ( natural size). 



Although in his day the limbs of the i, 2", transverse sections 

 Mosasaurus were imperfectly known, Cuvier 



1 The Monitors are a family of large lizards inhabiting the warmer parts of 

 Africa and Asia. They live near the banks of rivers, and some are altogether 

 aquatic. They often devour the eggs of crocodiles and aquatic birds. The 

 Nile Monitor, or Varauus, grows to a length of six feet. 



