394 Mr. A. S. Woodward on Fossil Fishes from 



moderate size. The opercular bones are smooth and the sub- 

 operculum seems to have been at least as deep as broad and 

 little inferior in size to the operculum. All the fins are small, 

 and conspicuous fulcra are preserved on the pectoral and 

 dorsal. The pectoral fin -rays, not less than sixteen in 

 number, do not appear to have been articulated except perhaps 

 at the distal extremity ; the pelvic fins, though imperfect, are 

 evidently relatively small and short-based and arise midway 

 between the pectoral arch and the anal fin. The rays of the 

 dorsal and anal fins exhibit distant articulations, and in each 

 fin there are a few short basal rays in front of the long ante- 

 rior rays on which the fulcra are arranged. The dorsal fin is 

 at least as deep as long, comprising about tvrenty-five rays 

 besides the basals, and is almost completely in advance of the 

 anal fin, which has a much greater extent and comprises not 

 less than forty, perhaps forty-five, rays in addition to the 

 basals. The whole of the trunk is covered with scales, and 

 there is a series of large post- claviculars attached to the hinder 

 border of the pectoral arch ; there are also one or two enlarged 

 ridge-scales at the origin of the dorsal and anal fins. The 

 scales of the flank are about as deep as broad, but become 

 much narrowed ventrally and reduced in size on the caudal 

 pedicle. One of the postclaviculars is marked with oblique 

 ridges and all the principal scales exhibit numerous fine 

 oblique pectinations at tlieir hinder margin, a character 

 gradually becoming obsolete on the caudal region ; apart 

 from the pectinations, all the scales are smooth. The lateral 

 line is conspicuous. 



Generic Determination. — The absence of the tail renders it 

 impossible to determine with certainty the family position of 

 the specimen just described; but it may be placed either in 

 the comprehensive family of Pala^oniscidse or in the Cato- 

 pteridse. Before the discovery of the species of Dictyopyge 

 in the Hawkesbury Beds of Australia* it would have been 

 concluded that such a head as is possessed by the South- 

 African fossil could only belong to a Palajoniscid and 

 undoubtedly implied a strongly heterocercal tail. The 

 Hawkesbury fishes, however, have most distinctly the same 

 type of head, combined with a remarkably atrophied hetero- 

 cercal tail, such as occurs in Dictyojyyge and Catopterus. No 

 decision as to the genus can therefore be arrived at until the 

 caudal extremity is discovered. If the fish is a Palffioniscid 



* Smith Woodward, " The Fossil Fislies of the Hawkeshury Series at 

 Gosford," Mem. Geol. Surv. N. S. Wales, no. 4 (1890), pp. 1(5-22, with 



