BUDLEIGH-SALTERTON PEBBLE-BED. 349 



22. Strophomena Edgelliana, Dav. B. S. Sup., PI. XXXIX, figs. 5 — 7. 



Strophomena Edgelliana, Dav. Quart. Journ. Geol. Soc, vol. xxvi, p. 86, pi. vi ; 



figs. 5—7, 1869. 



Transversely semicircular, with expanded angular extremities ; hinge-line as long as 

 the greatest breadth of shell. Ventral valve slightly convex ; area narrow, divided in the 

 middle by a triangular fissure. Dorsal valve very slightly convex, almost flat ; surface 

 marked by numerous fine, thread-like bifurcating striae, or with a smaller and shorter 

 one between each of the larger pair. In the interior of the ventral valve there is a small 

 tooth on either side of the base of the fissure, while the muscular impressions form a 

 small saucer-shaped depression surrounded by a raised margin ; this depression is about 

 as wide as long, or about one fourth of the width of the shell, notched in front, and 

 divided along the middle by a broad angular ridge. In the interior of the dorsal valve 

 there exists a small bilobed cardinal process ; slightly projecting, deviating, socket-ridges 

 are also visible. Under the cardinal process a raised hollow, roof-like ridge extends to a 

 little distance before becoming forked; on either side of the ridge are situated the 

 muscular scars. 



05s. — Several internal casts, as well as an external impression, of this interesting 

 species have been found by Mr. Vicary. It bears a good deal of resemblance to the 

 Leptana Dutertrii from the Devonian Limestone of Perques, near Boulogne-sur-Mer, 

 both in its exterior shape and interior arrangements, and I believe it to be a Devonian 

 species. I have named it after my friend Major Wyatt-Edgell, to whom we are indebted 

 for the discovery and publication of several interesting Budleigh species and specimens. 



23. Strophomena Budleighensis, Dav. B. S. Sup., PI. XXXIX, figs. 4, 4 a, 5. 



Strophomena Budleighensis, Dav. Quart. Journ. Geol. Soc, vol. xxvi, p. 86, pi. iv, 



fig. 1, 1869. 



Of this species a remarkable internal cast of the ventral valve was figured and 

 described by myself in* 1869. Since then no additional examples seem to have been 

 found. It is convex, semicircular, and about as wide as long, or a little longer than the 

 width of the shell. Area moderately wide, marked with perpendicular parallel lines, and 

 with two deep circular pits (elevations on the cast), one on each side of the centre, 

 divided by a small flattened space. The saucer-shaped muscular scars are large, and, in 

 the shell, divided by a median ridge. 



46 



