NORTH STAFFORDSHIRE COAL FOSSILS. 241 



rounded terminations. The dorsal fin is large and triangular, 

 the anal fin of the same size and placed directly opposite 

 to the dorsal fin. The dorsal fin in this genus is much 

 nearer the tail than in the genus Palasoniscus. In this respect, 

 Cycloptychius resembles the genus Catopterus, Redf. 



Position and locality : Deep mine ironstone, Longton. 

 GENUS GYROLEPIS, AGASSIZ. (Ref., Poiss. Foss., vol. 2.) 



This rare genus is represented in this coalfield by one 



species, and this occurs only in a very fragmentary condition. 



It is possible that these fragments belong to a species 

 described by Agassiz (G. Raukmii). 



Position and locality : Knowles ironstone, Fenton ; 

 Cockshead ironstone, Adderley Green. 



FAMILY ACANTHODEI, AGASSIZ. 

 GENUS ACANTHODES, AGASSIZ. 



Acanthodes Wardi, Egerton. (Ref., Quar. Jour. Geol. 

 Soc., vol. xxii., pi. xxiii.) The genus Acanthodes is not 

 uncommon in the Devonian formation, but it is exceedingly 

 rare in the Carboniferous rocks. Only three species have 

 hitherto been found in the latter. The average length of the 

 species under notice is from eight to nine inches. Specimens 

 of a larger size, which may represent a different species, have 

 been found. The body of the fish is covered with small 

 scales, smooth on their external surface, and covered with 

 a thick coating of ganoine : near the head they decrease in 

 size, and. present a skin-like appearance : they increase in 

 size in the caudal half of the fish. The pectoral, ventral, 

 T 



