﻿SUPPLEMENT, PLATE XII. 



All the figures in this Plate are copied from those drawn by Mr. West, and published 

 in the ' Proceedings of the Somersetshire Archaeological and Natural History Society,' 

 1854. They illustrate specimens in the Collection of Charles Moore, Esq., F.G.S. 



Fig. 



1 — 5. Thecidium granulosum, Moore. 1. Perfect shell, enlarged. 2. Interior of 



ventral valve, enlarged. 3. Interior of dorsal valve, 

 enlarged ; m, the perfect calcified supra-membraneal 

 disk ; s, septum. 4. Another enlarged dorsal valve, 

 showing the bridge, visceral cavity, loop, granulated 

 ridge, and solid portion of supra-membraneal disk- 

 5. Interior of dorsal valve, enlarged. Inferior 

 Oolite, Dundry. (P. 110.) 

 6 — 9. „ Forbesii, Moore. 6. Perfect shell, enlarged. 7. Imperfect or 



. worn specimen (dorsal valve), enlarged. 8. Interior 

 of ventral valve, enlarged. 9. Interior of dorsal valve, 

 enlarged. Inferior Oolite, Dundry. (P. 109.) 



10 — 14. ,, serratum, Moore. 10. Perfect shell, enlarged, showing the ex- 

 panded base of attachment. 11. Enlarged interior 

 of ventral valve, showing internal ribs and bosses on 

 the edge of the valve, muscular impressions, teeth, and 

 deltidium. 12. Dorsal valve, enlarged, showing per- 

 fect supra-membraneal disk, &c. 13, 14. Enlarged 

 dorsal valves. Inferior Oolite, Dundry. (P. 108.) 



15 — 20. „ duplication, Moore. 15,16. Perfect shell, enlarged. 17. Interior 



of ventral valve, enlarged. 18. Interior of dorsal 

 valve. 19, 20. Dorsal valves, enlarged. Inferior 

 Oolite, Dundry. (P. 108.) 



21 — 24. ,, septatum, Moore. 21. Perfect shell, enlarged. 22,23,24. Dorsal 



valves, enlarged. Inferior Oolite, Dundry. (P. 109.) 



25 — 26. „ triangulare, Moore. 25. Perfect shell, enlarged. 26. Interior of 



dorsal valve, enlarged. Inferior Oolite, Dundry. 

 (P. 106.) 



