33 Dr. R. H. Traqnair — JVeiv Carboniferous Fish-remains. 



PleuracantJius elegans, n.sp. 



Length of a perfect specimen 2^ inches ; straight, tapering, finely striated at the 

 base, smooth and polished towards the extremity, a ■well-marked delicate groove 

 running however along the whole length on each side close to the origin of the 

 denticles. Denticles 26 on each side in two opposite rows, extending move than two- 

 thirds the length of the spine, rather delicate, very oblique, with long flattened bases 

 and ganoid rounded-conical tips. 



The above described pretty little spine was lent to me by my friend Mr. Eobert 

 Kidston ; and in my owti collection are two others, of which one, nearly entire, would 

 be originally of the same size, and corresponds closely in external characters, while the 

 other is a fragment of a somewhat larger spine, and has the denticles somewhat more 

 closely placed, or with relatively shorter bases. 



Diplodus parviilus, n.sp. 



Although there is no doubt that the teeth of Pleuracanthus were generally identical 

 with those known as J)i/jlodus, and although the common Coal-measui'e Diplodus 

 ffibbosus probably belonged to the same species as bore the spine known as 

 Fleuracanthus Icevissimits, nevertheless so long as these remains occur in so scattered 

 a condition there must be insuperable difficidties as to accurately determining the spines 

 and teeth which ought respectively to be classed together as belonging to the same 

 species. Both generic names must therefore I fear continue to be used for some time 

 to come, and as regards the Diplodus now to be described, though it may very possibly 

 belong to the same fish as Fletiracanthns elegans, we have no evidence of the fact 

 beyond their occurrence in the same beds. Height from base to apex of cusps 

 |- to f inch. Base rounded, thick and high in front, thin behind, concave below, 

 with a knob or prominence at the anterior margin, and showing on the upper 

 surface a rounded flattened boss behind the origin of the cusps. Anterior surface 

 of base smooth, rounded, developing a more or less distinct carina, which ends 

 above on a small boss or knob between the cusps ; this knob being usually divided 

 or notched into several minute rounded lobules, but there is no median cusp or 

 denticle. Cusps two in number, strong, conical, diverging from each other, and also 

 bent more or less backwards, carinated or trenchant on each side, and frequently 

 showing towards their apices a few additional and fainter carinse or ridges, both 

 on their anterior and posterior siu:faces. Very frequently one cusp is somewhat 

 longer than the other, 



This small Diplodus is easily distinguished from D. ffibbosus by having between 

 the cusps in front a small blunt lobulated boss, instead of a large pointed denticle. I 

 have at present more than forty of these little teeth before me collected at different 

 times, all of which agree in this prominent character, and difi'er only in trivial matters 

 of detail, such as the relative prominence of the carina of the anterior surface, which 

 indeed is sometimes obsolete. 



Euctenins elegans, n.g. and sp. 

 Tooth (?) J inch in length by ^ in depth, somewhat elliptical in shape, convex on 

 one siu-face, concave on the other, with one margin nearly straight, or with a slight 

 sigmoidal curvature, the opposite margin evenly convex, one extremity rounded, the 

 other narrowing to a point. The convex margin is divided in a comb-like manner 

 into a series of closely placed acutely pointed denticles, fifteen to seventeen in number, 

 and obliquely directed from the rounded towards the pointed extremity of the fossil. 

 Counting from the former extremity, where they are very short, the denticles gradually 

 increase in length to the thirteenth, which measures -^g inch, whence they again 

 diminish. Surface smooth. 



Dipnoi. — Ctemdus angustidus, n.sp. 



Palatopterygoid bone about i-g inch in length, dental plate very narrow, bearing 

 three, sometimes four, closely placed ridges, all passing forwards and slightly diver- 

 gent or radiating from behind. Inner ridge longest, the succeeding ones becoming 

 successively shorter ; all are divided throughout their whole length into small bluntly 

 pointed conical dental tubercles, and covered with a brilliant layer of gauoine. No 

 mandibular teeth have occurred. 



Of this minute and peculiar form of Ctenodus I have at present five specimens, all 

 of nearly the same size. It is easily distinguished from any known species of 



