ACANTHODES PEACHI. — A. CORIACEUS. 



59 



Locality. — This specimen was discovered by Mr. Peach about 

 four years ago in a quarry of the Old Eed Schist belonging to the 

 Earl of Caithness, near Barragill. It is now in the Museum of 

 Practical Geology in Jermyn Street. 



Plate YI. Figs. 3, 4, 5. 



ACANTHODES CORIACEUS. 



This singular little fish is another of the novelties produced at 

 the Aberdeen meeting by Mr. Peach. It is not without hesitation 

 that I refer it to the genus Acanthodes, but as the only alternative 

 would be to establish a new generic definition, the preferable course, 

 it appears to me, is the one thus adopted, since it is better to defer 

 the introduction of a new title until good and sufficient materials 

 substantiate its necessity, than to enter a new generic name on the 

 list, already overcrowded, which may hereafter be found to be 

 unnecessary. 



Description.-— The unique specimen of this fish discovered by 

 Mr. Peach scarcely exceeds 1 inch in length. It reposes on the left 

 side, having the ventral surface slightly upturned so as to display 

 all the fins. It will be seen on referring to the enlarged represen- 

 tation most accurately delineated by the practiced and skilful hand 

 of Mr. Dinkel, that the arrangement of the several fins is in close 

 correspondence with the fin formula of the genus to which I have 

 referred it. There are two pectoral fins, two ventral fins, one 

 dorsal, and one anal fin, all armed with spines. The pectoral 

 spines are the longest, and the ventral spines the shortest of the 

 series. The dorsal and anal spines are intermediate in size, and 

 both of the same length. The body of the fish is more slender and 

 the fins more distant from each other than the corresponding parts 

 of Acanthodes Peachi. The dorsal fin is also more remotely placed 

 than in that species. These discrepancies forbid the idea I once 

 entertained that it might possibly be the fry of that species. The 

 most striking feature of this fish is the integumental covering. It 

 has all the appearance of a thick corrugated skin, with here and 

 there a trace of very minute scales. These are most evident near 

 the caudal extremity, and a group of them from this spot has been 

 carefully delineated by Mr. Dinkel. If the surface here seen be 

 the true exterior layer, and not the result of decomposition, it 

 would appear to be more granular than the coating of other 

 Acanthodean scales. 



