106 GANOID FISHES OF THE CARBONIFEROUS FORMATION. 



Palaeoniscid scale. On their attached surfaces these scales are smooth, and perfectly 

 destitute of the vertical keel, articular spine and socket found in normal Palaeoniseidie 

 and in most other rhombic scaled " Ganoids." The outer surface shows, posteriorly, 

 a free ganoid and sculptured area, occupying about one third of the entire space, the 

 remaining covered portion being dull, and, when examined by a strong lens, showing 

 very delicate concentric lines of growth. The exposed area is covered with fine, rounded, 

 brilliantly ganoid ridges, raised above the general surface, closely set, subparallel, and 

 proceeding across the surface to the posterior margin without convergence; they are 

 frequently intercalated, but more rarely appear to bifurcate. When examined by a lens, 

 these ridges, where the surface is abraded, appear to be hollow internally, with only 

 a very thin external covering, their tubular interiors being filled with white carbonate of 

 lime. 



Observations. — The first traces of this most interesting fish which came under my 

 notice, consisted of certain isolated scales from the Borough Lee Ironstone, which, on 

 account of their rounded contour, extensive overlapped area, and closely striated free 

 surface, I considered to belong to a new species of Ccelacanihus, which I accordingly, 

 in the beginning of the year 1881, named C. striatus. Towards the end of the same 

 year, however, I was startled to find that these scales belonged, not to a Coelacanthus at 

 all, nor even to a Crossopterygian, but to a fish, which in other respects was of typically 

 Palseoniscid structure. The error was no doubt a serious one, but also one which I 

 think any person who looks at the detached scales — thin, rounded, deeply imbricating 

 and delicately striated on their free surfaces, as they are — will readily be disposed to 

 excuse. And, as it turned out, the fish was of much greater interest than merely a new 

 species of Coelacanthus. For our knowledge of the British Palaeozoic fauna was enriched 

 by the addition of a remarkably aberrant form of Paloeoniscidae, and one which shows 

 not only how dangerous it may be to found conclusions on fragmentary remains, but how 

 small may be the systematic value of the mere external shape of the scales of " Ganoid " 

 fishes. For this aberrant form I accordingly, in November, 1881, founded the new 

 Palseoniscid genus Cryphiolepis. 



But the occurrence of a Palaeoniscid with rounded scales is not an isolated 

 phenomenon. Already, in 1875, 1 Prof. A. Fritsch, of Prague, had discovered in the 

 Lower Permian Gas Coal of Kounova, in Bohemia, a small fish, which he briefly noticed 

 as follows : 



" (Nov. gen.) Kounovensis : 1st eine neue Gattung von Fischen, die bei dem 

 Gesammthabitus eines Palaeoniscus mit Cycloidenschuppen versehen ist. Die Schwanz- 

 liosse ist heterocerc, die Kiefern mit grossen spitzen Zahnen versehen." 



For this new and interesting form Prof. Fritsch proposed, in 1877, 2 the name 

 Splicerolepis, which he afterwards, in the " Heft " of his great work on the Permian 



1 ' Sitzuugsberichte der k. bohni. Gesellsch. der Wissenscliaften,' Miirz 19, 1875. 

 - Ibid., January, 1877, also March, 1879. 



