ATHYRIS. 19 



Athyris? Bartoniensis (11. sp.). PI. Ill, fig. 23. 



Spec. Char. Rhombic, with rounded angles, wider than long. Valves moderately 

 and uniformly convex to about half their length, the remaining portion of the 

 dorsal valve being trilobed, a concave space separating the central from the lateral lobes. 

 A shallow sinus exists towards the front in the ventral valve ; beak not much produced. 

 External surface smooth, marked only by lines of growth. 



Length 2i inches, width 3 inches, depth 1 inch 2 lines. 



Obs. Of this remarkable species I have seen but one example, discovered by Mr. 

 Lee, in the Middle Devonian limestone of Barton, near Torquay. It is not quite perfect, 

 but by its dimensions and shape is so different from any other Devonian Athyris ? with 

 which I am acquainted, that I have ventured to give it a separate designation. 



Athyris ? (n. sp. ?). PL IV, fig 4. 



We find in the Lower (?) Devonian grits of Looe, in Cornwall, distorted internal casts of 

 a remarkably shaped shell, which we suppose to belong to the genus Athyris, but they are too 

 imperfect to admit of specific determination. In shape the shell is somewhat transversely 

 pentagonal, about one inch one line in length, by two inches two lines in width ; the valves 

 are moderately convex, with a shallow sinus in the ventral one ; the beak is moderately 

 produced, and there appears to exist a flattened space between its ridges and the hinge- 

 line. I cannot venture to propose a specific denomination on such incomplete material, 

 but better specimens may perhaps turn up now that the attention of collectors will have 

 been called to the subject. M. Bouchard thinks it might belong to Spirifera curvata, a 

 common Eifel species ; but the obtuse hinge-line appears to me more like that of an 

 Athyris than of a Spirifera. I may however be mistaken in my appreciation of the matter. 



? Athyris Newtoniensis (n. sp.). PI. Ill, fig. 22. 



Spec. Char. Shell transversely oval, wider than long, valves almost equally convex, 

 without fold or sinus ; beak moderately produced, and truncated by a foramen ; 

 beak-ridges sharply defined, leaving a flattened or concave space between them and the 

 hinge-line. External surface smooth, marked only by concentric lines of growth. 



Length 1 inch 9 lines, breadth 2 inches 4 lines, depth 1 inch. 



Obs. This shell was discovered by Mr. Champernowne in the Middle Devonian lime- 

 stone of Woolborough quarry, near Newton Abbot, Devonshire. 



