PLATE XII. 



Sphenotus ? soLENiFOEMis, Goldfuss, sp. (Page 84.) 



Fig. 



1. Specimen, mucb worn, but showing the anterior muscle-scar, and the flattened posterior^slope. 



la. Upper view, showing the umbones and the posterior gape. Locality? Mantell Collection, 

 British Museum. 



CucuLL^A DEPEESSA, Phillips. (Page 111.) 



2. Very large and long specimen, slightly displaced or squeezed, so that the umbo of the right valve 



has come into view behind the other. Marwood. Museum of Practical Geology. 



3. Phillips's type, which is shorter and much more curtailed behind. 3 a. Upper view. Marwood. 



Museum of Practical Geology. 



Pahallelodoit pygm^us, Wliiteaves, var. infans, n. v. (Page 112.) 



4. 5. Two minute casts, which seem to vary in length, one of which shows the posterior teeth, X 10. 



Poleshill. Porter Collection. 



Paballelodon priscxts, Ooldfuss, sp. (Page 113.) 



6. Cast of a left valve, x f . Ironpost. My Collection. 



MoDiOLOPsis, sp. (Page 114.) 



7. Left valve, much obscured by matrix, x 2. South Cave, Baggy Point. Museum of Practical 



Geology. 



Ctenodonta? tensa, n. sp. (Page 104.) 



8. Specimen showing the ornament, the subaugular posterior side, and signs of the lateral teeth, 



which seem to have pierced the thin surface, x f . Sloly. Barnstaple Athenaeum. 



9. Cast of a perfect, but very doubtful specimen, showing the teeth, x 2. da. Hinge-line, x 7. 



Barnstaple. Museum of Practical Geology. 



Ctenouonta (Koenenia), of. OBSOLETA, Ooldfuss, sp. (Page 106.) 



10. Cast, showing the large anterior teeth, but having lost almost all the posterior part of the hinge, 



X 2. Baggy Point. Museum of Practical Geology. 



Ntjculites ? LATissiMus, Phillips, sp. ? (Page 107.) 



11. Cast of right valve, showing the teeth and the clavicular ridge, X 2. 11 a, surface of the same 



valve drawn from a wax impression of its mould, X |. 11 h. End view, x 2. Fremington. 

 Barnstaple Athenseum. 



Ctenodonta (PALiEOifEiLo) LiEATA, Phillips, sp. (Page 100.) 



12. Interior of right valve, showing hinge, x 3. Baggy. Museum of Practical Geology. 



13. Eight valve, vertically compressed, x 2. 13 a. Portion of surface, the longitudinal lines of which 



are probably induced by pressure, x 15. Barnstaple. Woodwardian Museum. 



