102 PEOCEEDINGS OF THE GEOXO&ICAl SOCIETT. 



VII. Appindesc.'— Descripiiow of the new Fossils of the Hollyhush 

 Sandstone and Black Shale. 



1. Seepulites eisttjla, spec. nov. Fig. 7. 



Cylindrical, straight, tapering very gradually to a point; shell 

 thin, smooth. Length 1 inch to 1| inch ; diameter about 1 Hne. 



Position. — In the greenish-coloured upper beds of the Hollybush 

 Sandstone. 



2. LijiTGirLA PTGM^A, Salt., spec. nov. Pigs. 8 a, 8 6. 



Minute, subcylindrical, gibbous ; beak somewhat obtuse ; anterior 

 margin truncate; shell thin; surface finely striated transversely. 

 Length Jg-, width -^ inch. 



Position. — In the Black Shales. 



3. LlNGXTLA SQUAMOSA, SpeC. UOV. 



Triangular, broad anteriorly, compressed ; beak acute ; anterior 

 margin truncate ; shell thick, strongly grooved from side to side by 

 imbricating lines of growth. Length \ inch. 



Position. — In the light-brown felspathic sandstone of the Holly- 

 bush series. 



4. Oboleila Philxipsi, spec. nov. Pigs. 10 a, 10 h, 10 c. 



Semicircular, slightly broader than long; hinge-line straight, 

 nearly equal to the greatest width of the shell. Yentral valve 

 prominent at the beak, depressed near the margin ; beak smaU, 

 round, pointed, and situated close to the posterior margiu. Dorsal 

 valve evenly convex, slightly depressed at the angles ; umbo obtuse. 

 A slight mesial depression towards the anterior border in both valves. 

 Surface marked with numerous moderately fine, sharply defined, 

 rather unequal, concentric striae, at about their own width apart. 

 Length of a large specimen i inch, width ^ inch. 



The sheU-structure, where the outer layer has become exfoliated, 

 is strongly punctate. 



Position. — In the felspathic sandstones of the Hollybush series. 



5. Obolella Salteei, spec. nov. Pigs. 9«, 9 6. 



Compressed, subtriangular to nearly round, rather broader than 

 long ; shell thin ; surface grooved concentrically by a few inequidis- 

 tant, strongly marked lines of growth, and by numerous finer lines 

 which are distinct only on the sides of the shell. Length usually 

 about 5 inch, width slightly more. 



Position. — In the Black Shales. 



