152 GANOID FISHES OF THE CARBONIFEROUS FORMATION. 



between tlicm. Tlic siisj)cnsoiiuiu is oblique j the operculum is broad, but with 

 its inferior margin sloping obliquely uj)vvar(ls so as to make an acute angle with 

 the anterior, and an obtuse angle with the posterior margin. Correspondingly, 

 the superior margin of the subopercuhim slopes vciy obliquely upwards and backwards, 

 its anterior margin being short and the posterior one long and rounded. The upper 

 limb of the preoperculum is broad and triangular, the lower one narrow. I see no 

 markings on these opercular bones save a few concentric striae. The maxilla is of the 

 ordinary Palaeoniscoid shape, but in none of the specimens are its markings clearly 

 shown. The mandible (PI. XXXIII, fig. 10) is comparatively short, and is ornamented 

 with prominent ridges which run obliquely forward so as to touch the upper or dentary 

 inargin at very acute angles. I have not observed the teeth. 



The scales are small, rhombic, and with the usual Palaeoniscoid mode of articulation. 

 It is extremely difficult to make out accurately the character of their outer surfaces, 

 which seem to be ornamented with excessively minute and faintly marked ridges and 

 furrows, bearing obliquely in a direction downwards and backwards. 



s.op. _ 



^ — ^ mn 



FlO. 8. — Skctcli of tlie bones of tlie si<le of tlie lieail of Rhadinichlhi/s Phnifi, Ti"iq. Enlarged by one-half, 

 and sligbtlv restored, from a specimen from Burnlej in the British Mnscum, No. P. 7989. o}]. operculnm ; 

 s.op. subopercuhim; mn. niamlible. 



Observations. — In my first notice of this strange little Palaeoniscid I placed it only 

 provisionally under Ttliadiniclitliys, and stated that probably a new genus would 

 ultimately have to be instituted for its reception. Certainly, so far as I am aware, we 

 do not as yet know the conformation of the rays of the pectoral fin, and the peculiar 

 large development of the ethmoidal region of the cranium is not found in any other 

 species of the genus, yet it seems to me now to be better to allow it to remain, as 

 originally [)laced, in the genus Bhadiiiicliflii/s. As regards the relative position of the 

 dorsal and anal fins, they are also situated exactly opposite each other in Bhadiniclithys 

 Macconochii, and I should not think of removinn; it from its oenus on that account. 



Geological Position and Localities. — Coal Measures. The best specimens I have 

 seen, including the one figui'ed, were collected by the late Mr. John Plant, of the Royal 

 Museum, Salford, who obtained them at Collyhurst, near Manchester; these are now 

 in the British Museum (Natural History). Others, less ])erfeet, were found by the late 

 Mr. Ward in the Deep Mine Ironstone Shale, Longton, and are now also preserved in 

 the National Museum. The species has been also collected at Burnley, Lancashire, 

 by the late Mr. George Wild, and Mr. E. D. Wellburn has recorded it, though with a 

 query, from the " Better Bed " Coal, Low Moor, Yoikshire. 



