﻿ACANTH0D1DJE. 



9 



P. 236. Fragment, showing circumorbital plates ; Longton. 



Weaver Jones Coll. 



P. 1326. Caudal region of a large fish, and the greater portion of 

 two small fishes ; Longton. Egerton Coll. 



P. 1327. Portion of head and branchial arches, being the counter- 

 part of the specimen figured by Egerton, loc. cit. fig. 2 ; 

 Longton. Appearances in this fossil suggest that the gill- 

 clefts were well separated by narrow bands of scale- 

 covered skin. Egerton Coll. 



P. 3250. Imperfect specimen of moderate size, and the caudal region 

 of a small individual; Longton. EnnisJcillen Coll. 



P. 5178. Well-preserved caudal region ; Longton. Purchased, 1885. 



An Acanthodian spine from the Coal-Measures of Buxiere-les- 

 Mines, Allier, France, closely resembling the pectoral of Acanthodes 

 wardi, is named Onchus simplex, TL E. Sauvage, Bull. Soc. Geol. 

 France, [3] vol. vi. (1878) p. 625, pi. xi. fig. 4. Similar spines, of 

 small size, also occur in the Coal-Measures of Nova Scotia (Geol. 

 Survey Museum, Ottawa, and Bedpath Museum, Montreal). 



Acanthodes nitidus, sp. nov. 



Type. Imperfectly preserved fish ; British Museum. 



Body much elongated and slender, the maximum depth being 

 contained about six times in the total length. Pectoral fin-spines 

 broad, much laterally compressed, with a single groove and faint 

 ridge nearly parallel to the anterior border and disappearing dis- 

 tally ; other spines similarly grooved but somewhat more tumid in 

 the proximal half. Pelvic fin-spines relatively small, about one 

 third as large as the pectorals, situated halfway between the latter 

 and the anal. Anal fin-spine at least half as large as the pectoral, 

 larger than the dorsal, which is placed immediately behind. Scales 

 smooth, the surface faintly excavated or flat. 



So far as known, this species is readily distinguished from the 

 closely allied A. wardi by the relatively larger size and somewhat 

 more remote situation of the pelvic fins. 



Form. Sf Loc. Calciferous Sandstones : Dumfriesshire. 



P. 4057. The type specimen, being an imperfectly preserved fish, 

 0*22 in length, showing large portions of all the fin-spines 

 in position, and displaying the characters noted in the 

 diagnosis ; Eskdale. Purchased, 1883. 



