﻿56 GANOID PISHES OF THE CARBONIFEROUS FORMATION. 



family. The stout lower jaw measures If inch in length ; it is injured across the middle ; 

 and indeed only the front part of it, about inch in extent, is perfect ; and this 

 displays on its margin several teeth. Four of these teeth are perfect, each measuring a 

 little less than -§- inch in length; they are slender-conical, rounded in transverse 

 section, smooth externally, and sharply incurved laterally. The portion of bone on 

 which they are placed is ornamented by fine, wavy, longitudinal ridges, passing into a 

 delicate tuberculation at the symphysis. Nothing more can be made out regarding 

 the cranial structure, save that a gently curved elevation, passing very obliquely 

 downwards and backwards, probably indicates the form and position of the hyomandibular 

 element. 



The position of the clavicle is indicated by a curved elevated line, just posterior to 

 where we should have expected to have seen the hinder margin of the interoperculum. 

 Immediately below this a small portion of the right pectoral fin is found ; and the few 

 rays which are exposed are seen to be traversed by numerous, closely placed joints. The 

 entire ventral fin is exhibited : its numerous rays are tolerably fine, and dichotomise 

 towards their extremities into very delicate divisions. The dorsal fin is situated far for- 

 wards, in advance of the middle of the back ; there being a rather greater space between 

 it and the caudal behind than between its anterior commencement and the posterior part 

 of the head in front. Its anterior margin is much injured, so that the apex is not seen, 

 and its height not ascertainable : judging from the length of the base, namely, 2f inches, 

 it must have been a fin of very powerful dimensions, and very considerably larger than 

 the anal. The latter is completely exhibited, it is acuminate in shape, and concavely cut 

 out behind; the base measuring If inch in length, and the depth of the fin being If 

 inch. Both of these fins have a very similar structure, the rays being very numerous, 

 pretty stout in front, more delicate behind, finely striated externally, and with very close 

 transverse articulations, the joints shorter than they are broad. The rays of the caudal 

 are, of course, very numerous ; the first twelve of the lower lobe are tolerably stout, the 

 rest finer, and in the upper lobe fringing the body prolongation they are very fine ; their 

 articulations are also very close, being mostly, as in the other fins, considerably shorter 

 than broad ; externally they present the same delicate and beautiful striation. 



Supporting the rays of the dorsal fin is a series of very short interspinous bones, 

 larger in front, smaller behind, expanded at their extremities, and narrow in the middle ; 

 below these we find clear evidence of a second set, placed between them and the neural 

 spinous processes. About the middle of the fish a few spinous processes are seen here 

 and there among the scales. The interspinous supports of the anal are distinctly seen, 

 at least towards the front part of that fin ; they are considerably longer and more slender 

 in their configuration than those immediately supporting the dorsal. The scales of this 

 species are of medium size, and unfortunately very ill displayed in the specimen, being 

 much broken and crushed up together. What is seen of them shows that they were 

 rather higher than broad in the fore part of the fish ; diminishing gradually in size, and 



