118 AUTUMNS ON THE SPEY. 



and deep fish. It was covered with large circular 

 scales, so enormous when compared with the size 

 of the animal, that a specimen not more than half 

 a foot in length, has heen known to exhibit scales 

 three-eighths of an inch in diameter, and in 

 another larger fragmentary example, whose entire 

 length would not have exceeded a foot and a half, 

 the scales were fully an inch across. These, when 

 examined with the microscope, reveal the most 

 delicate and intricate sculpturing. 



The Osteolepls or bony scale is nearly allied. 

 The scales, though less, are yet large in propor- 

 tion to the size of the animal. The position of 

 the fins is remarkable. The anterior portion of 

 the body seems to be destitute of them, but they 

 crowd together on approaching the tail. The 

 ventral fins are opposite to the space that occurs 

 between the two dorsals, and the caudal or tail 

 is unusually developed on the lower side. 

 These organs must have been marvellously con- 

 structed. In existing fishes, as Miller remarks, 

 " the membrane is the principal agent in propel- 

 ling the creature ; it strikes against the water as 

 the membrane of a bat's wing strikes against the 

 air ; but in the fin of the Ostcolcpis, as in those 

 of many of its contemporaries, we find the condi- 

 tion reversed. The rays were so numerous, and 



