124 GANOID FISHES OF TMR CARBONIFEROUS FORMATION. 



sliouldor-einlle to llic oriyiii of the lower lobe of tlie caudal tin, the scales which it 

 traverses being each marked with a slight ridge or elevation, which disturbs very con- 

 siderably the regularity of the jjroper striae of the scale. 



Bemarlcs. — The MS. name Ci/cIopfycMus carbonarius, devised by Prof. Huxley fortius 

 beautiful little fish, was adopted by Prof. J. Young in his brief description. Its 

 characters are so distinct that I think there is scarcely any danger of its being confused 

 with any other s])ecies. 



Geological Position and Localities. — An Upper Carboniferous fish principally found 

 in the Coal Measures (Deep Mine Ironstone Shale) of Longton and Fenton in North 

 Staffordshire, where most of the specimens known were collected by the late Mr. John 

 Ward, F.Gr.S. The species has also been recorded from Northumberland by Barkas and 

 from Yorkshire by Wellburn.^ The types are in the Ward Collection, British Museum. 



2. Cyci.optychius concentricus, Traquair. Plate XXVII, figs. 6—9. 



Ctclopttchius concenteicus, Traquair. Trans. Eoy. Soc. Edinb., vol. xxx, 1881, 



p. 37, pi. ii, figs. 17—20. 

 — —A. 8. Woodward. Cat. Toss. Fislies Brit. Mu?., 



pt. ii, 1891, p. 461. 



Speci/ic Characters. — Postero-inferior angle of flank-scales obtuse; ridges on the 

 scales j)roportionately coarser than in C. carbonarius ; nearly concentric on the flank- 

 scales ; no zigzagged line at posterior border ; scales of the back low and having in the 

 central area a few diagonal ridges passing obliquely from before downwards and back- 

 wards. 



Descri2}tion. — Attaining a length of 4| inches; the specimen shown in PI. XXVII, 

 fig. G, measures 4j inches. The length of the head is contained about five times, the 

 greatest depth of the body over six times in the total length up to the extremity of the 

 upper caudal lobe. The contour of the fish is therefore peculiarly slender and graceful, 

 the depth of the body continuing pretty uniform as far as the origin of the posteriorly 

 placed dorsal fin, whence it tapers to the moderately stout tail-pedicle. 



The head is somewhat elongated, with very oblique suspensorium, extensive gape, 

 anteriorly placed orbit and well-marked ethmoidal prominence. The sculpture of the 

 cranial roof-bones is not exhibited ; on the other bones of the head it is of a striated 

 character, but is only well seen in the case of the maxilla and mandible. The former has 

 its broad post-orbital portion covered with closely set ridges which pass into an irregular 

 tuberculation along the dentary margin ; the mandible, slender and tapering in shape, 

 has also a narrow band of tuberculation along its upper margin, but below this the 

 surface is striated with fine ridges which proceed diagonally from above downwards and 



* 'Proc. Yorks. Geol. and Polytechnic Society,' vol. xiv, pt. ii, 1901, p. 168. 



