PLATE XIII. 



Oethoceeas eutriohdm, Whidhorne. (Page 122.) 

 Fig. 



1. Specimen of the upper part of the shell containing the body-chamber; some- 



what compressed, but preserving the outer surface of the shell ; 1 a, 

 portion of the surface enlarged. Lummaton. Champernowne Collection. 



Oethooekas tenuisteiatum, Miinster. (Page 124.) 



2. Specimen retaining the test, though considerably weathered ; 2 a, portion of 



surface enlarged; 2 &, diagram of section. Wolborough? Torquay Museum. 



Oethoobeas Vioaeii, Whidhorne. (Pa^e 129.) 



3. A specimen retaining for the most part the external shell, though rather 



worn, but defective on the ventral side, where septa are exposed, and show 

 that the rings are three times as numerous as the chambers. The down- 

 ward convexity of the lowest septum, and the position of the siphuncle 

 are also seen. Wolborough. Museum of Practical Geology. 



4. A very large specimen retaining the external shell ; 4 a, portion of surface 



enlarged. Wolborough. Vicary Collection. 



5. Another medium-sized specimen, seen from the side, showing an obliquity of 



the rings. Lummaton. Lee Collection. 



6. 7. Portions of two small specimens ; 7 a, diagram of section. Lummaton. My 



Collection. 



Oethoceeas Vioaeii, Whidhorne, var. eductum. (Page 132.) 



8. Small specimen showing the increasing distance of the rings. Lummaton. 



My Collection. 



Oethoceeas Vioaeii (Whidhorne) ? (Page 129.) 



9. Ventral view of a specimen ; 9 «, lateral view, showing a great obliquity of 



the rings ; 9 h, diagram of section. Wolborough. Vicary Collection. 



Oethoceeas Robeetsii, n. sp. (Page 126.) 



10. Large specimen retaining the external shell, obliquely cut below to show the 



position of the siphuncle ; 10 a, portion of surface enlarged ; 10 h, nearly 

 longitudinal section of the lower part of the same specimen showing the 

 chambers and the siphuncle. It is to be noticed that the walls of the 

 chambers constrict the siphuncle, the apparent diminution of which, up- 

 wards, is due to the obliquity of the section. Wolborough ? Torquay Museum. 



11. Another specimen with slightly elliptic section. Wolborough. Museum of 



Practical Geology. 



12. Another specimen, partially retaining outer shell; 12a, portion of surface 



enlarged; 12 b, diagram of section. Lummaton. My Collection. 



13. Another large specimen, somewhat weathered, showing the downward convexity 



of the septum ; 13 a, portion of surface enlarged. Wolborough. Vicary 

 Collection. 



Oethoceeas eapieoeme, Sandherger. (Page 121.) 



14. Large and nearly perfect specimen which has no trace of any surface orna- 



mentation ; 14 a, diagram of section. Lummaton. Torquay Museum. 



15. Another specimen much worn, but retaining at one point indications of the 



external ornamentation ; 15 a, portion of the surface at this point, enlarged. 

 Wolborough. Museum of Practical Geology. 



