238 PROF. E. FORBES ON LOWER GREENSAND FOSSILS. 



rays, separated by strongly marked lines of growth, thus present- 

 ing a scalariform appearance. These markings become obsolete, 

 and towards the broader extremity disappear altogether. 



Var. ? There is a young Solen in the collection from the same 

 locality, which appears to be a variety differing in the more ex- 

 centric position of the beaks. Its surface is not sufficiently perfect 

 to present the characteristic markings. 



Note. The cast described and figured by M. A. D'Orbigny as Solen Robin- 

 aldinus, from the Neocomian of France, and that called Solen compressus by 

 Goldfuss, may be related to this species. 



5. Panopcea mandibula (Mya sp.) Sow. M. C. t. 43. 

 Loc. Atherfield, Hythe, Reigate. 



Var. /3. obliqua. P. obliqua D'Orb. T. C. pi. 352. 

 Loc. Atherfield. 



6. Panopcea plicata (Mya sp.). 

 Var. a. Sow. M. C. t. 419. fig. 3. 



Var. (j. Pholadomya Prevosti Desh. in Leym. pi. 2. f. 7. 

 Var. y. Pholadomya acutisulcata Desh. in Leym. pi. 3. f. 2. ? 

 Loc. Atherfield, Culver, Hythe, Reigate, Sandgate, Stopham. 

 Note. A very variable species, common to the upper and lower greensands. 



7. Panopcea elongata (Mya sp.) Roemer. Cret. Geb. t. x. f. 5. ? 

 Loc. Hythe, Pulborough. 



Note. Possibly only an elongated variety of the last. 



8. Panopcea neocomiensis (Pholadomya sp.) Leym. pi. 3. f. 4. 

 Loc. Atherfield. 



Note. The surface of this species is strongly granulated ; the granulations 

 are arranged in lines. Identified by comparison with French specimens. 



9. Panopcea ? 



Apparently a distinct species, but not sufficiently perfect for 

 certain determination. It is nearly sequilateral. 



Loc. Redhill, Reigate. 



10. Pholadomya gigantea (Pholas sp.) Sow. in Geol. Trans. 



2d ser. vol. iv. pi. 14. f. 1. 

 Loc. Court-at- Street. 



11. Pholadomya Martini. Sp. nov. PI. 2. f. 3. 



P. Testa obliqua, tumida, valde inaequilaterali, costis tuber- 

 culatis radiantibus ornata, sulcis transversalibus decussantibus ; 

 costis posterioribus approximatis, anterioribus distantibus. 

 Lon. 0|§ unc. Lat. 2^- unc. 



This species is common at Atherfield. It rarely attains larger 

 dimensions than those noted. It is almost always tumid and 

 oblique, with numerous longitudinal ribs, which are more or less 

 tuberculated by the intersection of lines of growth. These ribs 

 are widely set at the buccal extremity, and more distant at the 

 anal. In the Pholadomya gigantea, the ribs are most numerous 

 at the buccal end, and the shell is much broader. 



Loc. Pulborough, Atherfield. 



