JURASSIC AND TRIASSIC BRACHIOPODA. 217 



Rhynchonella Egretta, C. Moore. Somersetshire Archaeol. and Nat. Hist. Soc., 



vol. xiii, 1865-6; and Quart. Journ. Geo). 

 Soc, vol. xxiii, p. 477 1867. 



Shell small, about as long as wide ; valves moderately convex and somewhat flattened. 

 Dorsal valve divided into three almost equal portions, the central one forming a wide, 

 slightly raised and flattened fold. Ventral valve a degree deeper than the opposite one ; 

 sinus wide, of small depth ; beak pointed, incurved ; foramen small. Surface of valves 

 ornamented with a variable number of ribs, of which about twelve may be counted on 

 each valve, three or four occupying the fold and sinus. Proportions variable ; a large 

 specimen measured — 



Length 8, width 8, depth 5 lines. 



Obs. — This species has been well described and figured by M. E Deslongchamps, 

 and was found by him in the bed containing Leptana Davidsoni at May, near Caen, in 

 Normandy, where it was rather abundant. In England it was found by Mr. C. Moore 

 at Whatley, in the representative of the Fontaine-Etoupe Lias, and some specimens in the 

 Museum of the School of Mines in London are labelled Middle Lias, Chideock. 



223. Rhynchonella (?) Lopensis, Moore. Sup., PI. XXVII, figs. 8, 9. 



Rhynchonella Lopensis, Moore. Proceedings of the Somersetshire Archaeological 



and Nat. Hist. Soc, p. 114, pi. i, figs. 9, 10, 

 1855. 



Shell small, flattened, thickest at the umbone, triangular, nearly straight in front, 

 from whence it tapers to the beak. Deltidium triangular. Dorsal valve slightly 

 concave. Ventral valve proportionately convex. 



" This little species is from a bed of blue Oolitic Marl occurring in the neighbourhood 

 of Lopen, near Ilminster, where it is rare. In Mr. Davidson's Appendix (vol. i, p. 30) it 

 is named R. triangularis, but that name having been previously adopted by Wahlenberg 

 it has been altered." (Moore.) 



Obs. — I have seen two examples of this shell, the largest being two lines in length 

 by nearly three in width. Mr. Moore's figures give a faithful general representation of 

 his shell, but I fear it is not a Rhynchonella. The ventral valve is generally convex and 

 carinated, while the dorsal one is much depressed ; the beak triangular and pointed. I 

 could notascertain the exact form or position of the foramen. Both valves are very much 

 flattened, so that there is only a small space left between the valves for the accommodation 

 of the animal. 



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