COCCOSTEUS AND DINICHTHYS 



of a saddler's knife and the two eyes are placed 

 near the centre. Another fish is known almost 

 solely by the shields which covered the head or 

 head and body, one above and the other below. 



F.J,' 



Fig. 185. — The upper figure is a restored outline of the curious 

 Devonian fish, Coccosteus. It is about a foot and a half 

 long. The lower figure is a photograph to the same scale 

 of the lower jaw of a huge fish allied to Coccosteus foxuid 

 in the Devonian rocks of Ohio in the United States of 

 America. It is called Dinichthys, and must have been from 

 ten to twelve feet long. The above jaw and nearly 

 complete skulls are in the Natural History Museum. 



This is the Pteraspis (Fig. 187). The head or 

 head-and-body shields of these fishes and those 

 of Cephalaspis are found in immense numbers 

 in the hard gritty " cornstones " of Worcester- 



257 s 



