OF CREATION. 67 



the tenants of the sea in our own latitude ; but we are 

 now able to describe with more minuteness, if not so 

 vividly, the real nature of the animal. It was of small 

 size, not more than a few inches or a foot in length ; 

 its head and body were defended by strong plates of 

 bone coated with enamel ; and its shape and propor- 

 tions were singularly unlike those of ordinary fishes ; 

 the head being small, and the body much flattened, but 

 swelling out immediately at the junction of the head 

 and neck, and gradually tapering thence towards the 

 tail. From the junction of the head and body there 

 extended that pair of singular paddles or wings from 

 which the genus has been named, and which have been 

 supposed to answer the same purpose as the horns of 

 the crescent-shaped shield of the Cephalaspis, and 

 defend the animal from the attacks of its soft-mouthed 

 enemies. Besides these paddles, which were hard and 

 pointed, and nearly as long as the body, at least some 

 species of Pterichthys seem to have been provided 

 with another smaller pair, extending from the part 

 where the body is attached to the tail ; and it is 

 thought that this second pair of wings may be the 

 remains of anal fins, the other pair representing the 

 pectoral fins. The body, like the head, was certainly 

 covered on the upper side by hard plates accurately 

 fitting one another ; but the lower part both of the 

 head and body was probably defended by tough skin, 

 capable of distension, and enabling the creature to 

 swallow prey of large size. The position of the 

 mouth is not known with certainty, but it may have 

 been formed by a transverse slit, covered by thick 

 fleshy lips, situated round the edge of the plate which 

 defended the head ; this position, and the absence of 



