536 KEV. G. E. WHIDBOKNE ON SOME EOSSILS 



I have obtained several specimens of this shell from Dundry. 

 There is a fine specimen in the British Museum and two at Jermyn 

 Street from Leckhampton. 



Dimensions. About 10 lines in length and 13 lines in width. 



The central prominent and flattened umbones, together with the 

 ribbed central and smooth lateral portions of the surface, serve to 

 distinguish this shell, and I have not met with any species with 

 which I have been able to identify it. The specimen figured, being 

 an injured one, hardly shows its characters so well as might be 

 wished. 



Tekebkattjla Tawneyi, n. sp. Plate XIX. figs. 12, 12 a, 12 b. 



Shell small, orbicular, flattened dorsally, convex ventrally. Beak 

 moderately incurved and protruding upwards. Foramen very large, 

 bounded by the summit of the dorsal valve. Deltidium absent. 

 Yentral valve moderately convex. Dorsal valve only slightly so. 

 Margins nearly circular. Slight indications of a very wide and 

 flat fold. Hinge-area small, linear. Surface covered with numerous 

 fine rounded ribs, arranged in irregular groups by every third or 

 fourth one becoming more prominent; these lines reach and cover 

 the umbo. Shell-structure with exceedingly large and coarse 

 puncta, arranged in curving rows. 



I have found a single specimen of this beautiful little shell in the 

 upper beds of the Humphriesiantts-zone at Dundry. 



Dimensions. It is about 6 lines in length and width and 3 in depth. 



Dr. Davidson, who has very kindly examined the fossil, informs 

 me that he considers it to be new. 



In naming it after our much lamented friend, Mr. Tawney, by 

 whose admirable arrangement of the fossils in the Bristol Museum 

 I have been much helped in the examination of these shells, I can- 

 not help bearing witness to the greatness of his loss to science ; but 

 his persevering energy, accuracy of knowledge, and quickness of 

 observation cannot make his early death more regretted among 

 geologists than the kindness of his disposition, experienced by myself 

 on many occasions, has done among his friends. 



Rhabdocidakis Thukmaistnt, De Lor., var. kegkens. Plate XIX. figs. 

 13, 13a, 136. 



I have obtained a fragmentary spine of Rliabdocidaris from the 

 upper beds of the Hwnphriesianus-zone at Dundry, in which Man- 

 gotia Forbesii not unfrequently occurs, as well as other Echinoderms, 

 Thecidia triangularis, and some small sponges. It is much flattened, 

 with expanding sides, convex shoulders, and small neck. The upper 

 surface is covered by exceedingly numerous and fine nodulous lines, 

 which become coarser and more distant on the sides and lower sur- 

 face, down the centre of which runs a wide arching grove. The 

 shoulders are covered with coarser spines. 



Dimensions. Width about 1 inch, depth j inch. 



It appears very like Desor and De Loriel's figure of Rliabdocidaris 

 Thurmanni, in their ' Echinologie Helvetique,' t. 9. figs. 2-4, and 



