8 Mr. F. M'Coy on some new Fossil Fish 



The specimen described is a reniform, convex plate^ rather more 

 than half a hne thick, 1 inch 9 lines long and 1 inch wide, most 

 probably belonging to the side of the head ; not exactly agreeing 

 with any bone I know in shape, but most like an operculum. The 

 under surface is smooth (except the nucleus), the outer surface 

 closely sculptured as above-mentioned. This species has the cre- 

 nulations of the P. arenatus (Ag.), but the irregular, minute, 

 and frequently confluent granules of the P. undulatus (Ag.) ; it is 

 most nearly allied to the latter species, but the asperities, besides 

 being crenulated, are smaller, more irregular, and the confluent 

 ones more twisted and vermicular. The minute microscopic 

 structure resembles that of Psammosteus generally, that is, four 

 or five dense horizontal layers at the surface, beneath which the 

 substance is composed of large irregular cells, about half their 

 diameter apart, but irregularly arranged in the blastema. 



From the yellow sandstone shale of Fallaghloon, Maghera, 

 Ireland. 



{Col. Mr. Griffith at Dubhn.) 



Chelyophorus Griffithii (M'Coy). 



The specimens to which I give this name consist of a small jaw- 

 bone, resembling the glossohyal in shape, about W^ lines long, 

 obtusely pointed at the anterior end, and gradually increasing to 

 nearly 2 lines in depth towards the posterior extremity, which is 

 abruptly acuminated or wedge-shaped; the upper edge shows seven 

 or eight small, curved, smooth conical teeth, their length rather 

 more than twice their width, and the distance between them 

 rather greater than their length ; the surface of the margin has 

 three or four rows of slightly elongate, closely-placed tubercles ; 

 towards the middle and lower part of the bone the tubercles elon- 

 gate into short ridges, arranged in lines, which meet at an angle 

 of 45° along the middle of the side, the angle pointing back- 

 wards on the posterior half, and forwards on the anterior half, 

 so as to have a confused rhombic space at the middle of the bone ; 

 all the ridges and tubercles are glossy, very closely placed, and 

 finely crenulated at their margins. The second specimen is a 

 bone probably from the side of the occiput, resembling the por- 

 tions of Chelyophorus Verneuili (Ag.) in figs. 17 and 18. pi. 31a 

 of Agassiz, Monog. Old Ked, &c. ; the granulation of the scul- 

 ptured portion is rather more distinct, forming lengthened tu- 

 bercles in one part and subparallel ridges in another, and all mi- 

 nutely crenulated on the sides. The sculpturing of the two spe- 

 cimens is identical in character, both with each other and with 

 the old red Chelyophori, diff'ering from the C. Verneuili princi- 

 pally in the crenulation of the side of the tubercles. 



