DRYDENIUS MOLYNEUXI. 103 



hones ;ire ornamented with closely-placed, contorted, thread-like ridges; the jaws are 

 armed with apparently one row of comparatively stout stylo-conical, bluntly-pointed 

 teeth, which are slightly incurved towards the apex. In PI. XX, fig. 8, a magnified 

 view is given of the impression of a portion of the mandible, from a specimen in the 

 Royal Scottish Museum, showing the imprints of these teeth, while another specimen in 

 the same museum gives evidence of the presence likewise of large teeth of the same 

 character as those forming the splenial armature of the last described species. The 

 scales are proportionally large, with narrow overlapped surface; the exposed surface in 

 the flank scales (fig. 7) is marked in front with a few exceedingly delicate vertical grooves 

 or striae turning round below, parallel with the lower margin, the rest of the surface being 

 marked posteriorly with nearly equally minute transverse striae ending on very delicate 

 denticulations of the hinder margin — a nearly smooth space being left between this set 

 of transverse striae and the vertical one along the front. The scales become smaller and 

 more oblique posteriorly, the striation also fading away, though the marginal denticula- 

 tion remains as far back as the caudal fin. Vascular pores are rarely visible on the 

 ganoid exposed surfaces of the scales. The fins are not well preserved in any of the 

 specimens which I have seen. The pectorals are not visible; the dorsal (see PI. XX, 

 fig. 0) is nearly opposite the interval between the ventrals and the anal ; the caudal is, 

 of course, heterocercal. All seem to be rather few-rayed ; the rays are comparatively 

 coarse, with distant articulations, the joints being smooth, or ornamented with one or 

 two delicate sulci. 



Observations. — This well-marked species was discovered and recognised as undescribed 

 by the late Mr. John Ward, F.G.S., of Longton, who confided the specimens to me for 

 description with the request that I would name it Molyneuxi, after his deceased friend 

 Mr. Molyneux, well known as a collector of North Staffordshire Carboniferous Fossils. 

 It is the same fish to which I alluded, without description, as Microconodus Molyneuxi in 

 my essay on the structure of the Pala3oniscida3 (' Pal. Soc.,' 1877), but in 1888 I 

 referred it somewhat doubtfully to Gonatodus, stating that although it had certain 

 obvious resemblances to that genus, the teeth did not seem to exhibit the characteristic 

 second flexure at the apex. However, the discovery in a specimen, referable to 

 this species, of large teeth, apparently identical with the remarkable splenial teeth 

 of Drydenius insiynis, sheds a new light on the matter and induces me to class 

 "Molyneuxi" also as a member of the same genus. 



Geoloyical Position and Locality. — Only known from the North Staffordshire Coal 

 Measures, having been collected from the Deep Mine Ironstone at Longton by the late 

 Mr. Ward. The type specimens are in the British Museum ; others are in the Royal 

 Scottish Museum, Edinburgh. 



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