A GREAT PERMIAN DELTA 



5 6 7 



Fig. 12. Skull of Diplocaulus, showing 

 the upper and lower surfaces. 



Fig. 13. Restoration of 

 Diplocaulus. 



in the coal beds of South Joggins in Xova Scotia ; they wrapped them- 

 selves in armor and they hid themselves in the ground. 



It is possible to describe but a very few of the forms that are known. 

 Eryops was the largest of the amphibian tribe, with a length of about 

 eight feet; it was not unlike a great overgrown newt or salamander 

 with weak sprawling limbs that could not raise the body from the 

 ground, except by a great effort. The skull had a length of two feet 

 and a half in the largest specimens and the lower jaw was hinged at 

 the posterior end of the skull, so that the animal had a most tremendous 

 gape. The jaws were armed -with sharp conical teeth, which in the 

 anterior portions of the jaws were developed into powerful tusks. Prob- 

 ably the animal played a somewhat similar part in the Permian waters 

 to that of the modern alligator, lying nearly covered in the water with 

 only the eyes and nostrils exposed, which were placed on the top of 

 the skull for the purpose, and gliding slowly upon its prey until within 

 a distance that made possible a sudden fierce rush which ended with 

 the passage of the victim down the capacious maw of the Eryops. 



Contrasted with Eryops, and probably frequently its victim, was the 

 small Diplocaulus. Though still imperfectly known, enough has been 

 made out about this animal to show that it possessed a form even more 

 grotesque than that of the high-spined reptiles. The head, as shown 

 in Fig. 12, was extremely flat and shaped like an exaggerated crescent 

 with strong horns or spines projecting to the rear from the posterior 

 corners. The eyes and nostrils were located far forward toward the 

 anterior end and were directed straight upward. The lower jaw was 



