PLATE II. 



Fig. 



1. Spirifer rostratus, Schl., the largest specimen known. 



2. ,, ,, from the Lias of Battle Down, near Cheltenham. 



Sp. punctatus (Buckman). 



3. „ „ an unusual form of this species. 



4. „ ,, from a specimen found in the Upper Lias, near 



Ilminster. 



5. ,, „ side view of a specimen from Ilminster. 



6. „ „ young shell. 



7. 8, 9. ,, „ variety, with undulations, or rounded false plaits : 



Spirifer pinguis of Zieten, non Sp. pinguis of 

 Sowerby. 

 10, 11, 12. „ ,, an unusual specimen. 



13. „ ., interior of smaller valve, as it would appear on 



separating the valves completely. 



14. „ „ side view of a specimen illustrating the spirals. 



15. ,, ,, interior of larger valve. 



16. „ „ enlarged illustration, showing the position and form 



of the central septum and dental plates of 

 larger valve, relative to the spirals in smaller 

 valve; also the lamella, or cross-piece uniting 

 the two spirals. 



17. „ „ enlarged illustration of a portion of the lamella, 



facing the sides of the shell, showing that on 

 that side there are no spines. 



18. „ ,, enlarged view of the inner side of the lamella of the 



spirals, illustrating the manner in which the 

 spines are placed. 



19. „ „ magnified portion of the exterior of the shell, show- 



ing the tubular spines and punctuation. 



20. ,, „ enlarged fragment, showing the form and position of 



the deltidium in two pieces. 



21. ,, „ magnified interior from a perfect specimen. In this 



figure a part of the smaller valve has been 

 removed, so as to show the position of the 

 spirals and cross-piece uniting them, as well as 

 the relative position of the central septum of 

 the larger valve and the position of the spines 

 on the portion of the spirals facing the front of 

 the shell. 



