138 GANOID FISIIKS OF TIIK CARBONIFEROUS FORMATION. 



'I'lie materials which 1 iiavc cxaiiiiiiccl, besides the type seales in the British Museum, 

 are : 



All imperfect Hsh which was in tl:c collection of the late l)r, J. R. S. Hunter, of 

 Braid wood, Lanarksliire.' 



Some specimens of disjointed remains in the collection of the Geological Survev of 

 Scotland. 



An imperfect fish (PI. XXXI, fig. 3) and some scales, three of which are represented 

 in the same plate (figs. 4 — G). These belong to the Royal Scottish Museum. 



The scales of the flank are nearly equilateral, the articular spine is well marked, the 

 covered area very narrow. The exposed surface is marked in the first place by a band 

 of fine grooves passing closely along the anterior and inferior margins, the remaining 

 and greater part of the area being occupied by more or less prominent ridges, which run 

 backwards in a direction nearly parallel with the upper and lower margins and end on 

 sharp denticulations of the posterior border. The usual number of these transverse 

 ridges and denticulations seems to be four or five, but in the scale represented in PI. 

 XXXI, fig. 4, which apparently belongs to the same species, no less than nine may be 

 counted. The scales on the belly are, as usual, low and narrow; posteriorly tliey also 

 get smaller and their distinctive sculpture less strongly marked. The [)ectoral fin is 

 moderate in size; its principal rays are unarticulated till towards their terminations; 

 the ventral fins I have not seen. The median fins are exhibited in the specimen repre- 

 sented in PI. XXXI, fig. 3. The dorsal and anal fins are in this example nearly opposite 

 each other, but it is the anal which aj)parently commences a little in front of the dorsal ; 

 this, however, I attribute to post-mortem deformation, as the scales are considerably 

 jumbled and as the two fins are seen in the position normal to the genus in a specimen 

 figured by Wellburn. Only the larger rays are seen and these are broken off before 

 dichotomisation ; the articulations of the rays are distant, and the joints smooth or with 

 one longitudinal furrow. The caudal fin shows the shape of the upper lobe pretty well, 

 but the rays of the lower one are broken up ; their articulations are distant. 



A specimen in the collection of the Geological Survey of Scotland shows, lying 

 together with a heap of the characteristic scales, the im{)ression of a ])ortion of the 

 cranial buckler, and from this impression it is evident that its surface was sculptured 

 with tolerably coarse ridges, passing here and there into tubercles. The position of the 

 orbit is clearly shown, below which is found the left maxilla seen from its inner surface 

 together with the impression of the outer surface of the mandible. The oral margin of 

 the maxilla is set with conical teeth, small indeed in the specimen, but large enough 

 considering the small size of the jaw. The mandible is slender and tapering, sculptured 

 with a few comparatively coarse ridges, which, as usual, pass forwards and also obliquely 

 upwards, meeting the dental margin at very acute angles ; its teeth are not exhibited. 

 Lastly, behind the mandible are several confused bony rays, the remains of the pectoral 

 ^ No doubt lost in the fire which destroyed the Kilmarnock Museum on November 26th, 1909. 



