PLATE VIII. 



Fig. 1. — Carbonicola gibbosa. From the roof of the Moss Coal, Fenton, 

 showing anterior end view and deep lunule. Collection of Mr. John Ward, F.G.S. 

 (Page 65.) 



Fig. 1 a. — The same shell. Lateral view. 



Fig. 1 b. — The same shell, showing the umbones, external ligament, and upper 

 surface. 



Fig. 2. — Carbonicola gibbosa. Another example from the same bed. Collection 

 of Mr. J. Ward, F.G.S. (Page 65.) 



Figs. 3 — 7. — Carbonicola subrotunda. A series from the Lower Coal-measures 

 of North Staffordshire, exact horizon not known, but some distance above the Hard 

 Mine Seam. The bed was passed through in sinking the Adderley Green Colliery. 

 My Collection. (Page 65.) 



Figs. 4 a and 5 a. — The upper surfaces, umbones, lunule, and external liga- 

 ments of figs. 4 and 5. (Page 65.) 



Fig. 8. — Carbonicola turqida. A typical specimen from Stubb's Mine, Bardsley. 

 My Collection. (Page 66.) 



Fig. 8 a. — The same specimen, seen from above. (Page 66.) 



Fig. 9. — Carbonicola turgida, — Showing the hinge-plate and interior of a right 

 valve. Stanley Main Seam, Wakefield. My Collection. (Page 66.) 



Figs. 10 — 12 a. — Carbonicola turgida. A series from the horizon of Stubb's 

 Mine, Bardsley. Presented to me by Mr. George Wild. My Collection. 

 (Page 66.) 



Fig. 13. — Carbonicola turgida. Coalbrookdale. My Collection. (Page 66.) 



Fig. 14. — Carbonicola turgida. A cast from the Splint Coal, Wishaw, in the 

 Braidwood Collection of Dr. Hunter. (Page 66.) 



Fig. 15. — Carbonicola turgida. A cast from the Ell Coal, Cambushlang. From 

 the same Collection. (Page 66.) 



Fig. 16. — Carbonicola turgida. — A cast showing muscle-scars from Shettleston, 

 in the Collection of Dr. John Young. (Page 66.) 



Fig. 16 a. — The same cast, viewed from above. (Page 66.) 



Fig. 17. — Carbonicola turgida. A young and shortened form from the Collec- 

 tion of Dr. John Young. (Page 66.) 



Fig. 17 a. — The same shell viewed from above. 



Fig. 18. — Carbonicola turgida. Coalbrookdale. My Collection. (Page 66.) 



Fig. 18 a. — The same shell viewed from the front, showing the deep heart- 

 shaped lunule. 



Fig. 18 b. — The same shell seen from above. 



Fig. 19. — Carbonicola turgida. A large example from the North Staffordshire 

 Coal-field. Horizon not known. My Collection. (Page 66.) 



Fig. 20. — Carbonicola turgida. Coalbrookdale, Madeley Court. A pretty 

 little shell, whose posterior end has not developed. In the Collection of the Wood- 

 wardian Museum, Cambridge. (Page 66.) 



Fig. 21 — 25. — Carbonicola turgida. A series of young forms from the roof of 

 the Moss-coal, Lane End Colliery, Fenton. My Collection. (Page 66.) 



