NATICA. 77 



7. DiDYMAjf. 4, l4:,Bolt. — K ollce et N. Campechensi similis, 

 sed callo umbilicali per sulciim diviso. — Glaitcina of Lamarck 

 not being the glaucina of Linna3us, this species has been 

 divided into several, under other names, by Reclnz, &c. 

 These are : Chemriitzii, Recluz {glaucina, Lamarck, not 

 Linnaeus), our f. 4 ; Petiveriana, Eecluz, with the callus a 

 little less produced; nnd LamarcJciana, Deshayes, our f. 14. — 

 These all differ from N. olla and camjoechensls in having 

 the projecting- umbilical callus divided by a grove. They 

 cannot be fairly separated from each other, and we follow 

 the arrangement of the British jMuseum in applying to them 

 the above resuscitated name. 



8. PROBLEMATicA, f. 54, Reeve. — Quam N. didyma magis 

 oblique elevata ; umbilico elongate; callo umbilicali angusto, 

 diviso. — The greater obliquity in form and the columnar 

 elevation of the callus may perhaps justify the separation of 

 this species. 



9. HERCULEA, f. 3, Jonas. — Magna globosa pallide fulva ; 

 spira exsertiuscula, anfractibus ad suturam angulatis, turn 

 declivibus ; apertura mag-na, labio externo superne producto, 

 sinuato ; columella arcuata, lata, callosa, parti m super umbi- 

 licum producta ; umbilico lato. — A large shell, differing from 

 the preceding group in form and in the callus, which is 

 scarcely extended into a lobe over the umbilicus. The whorls 

 are angular near the suture, and then slope outwards. 



10. Incei, f. 63, 64 (young), 101-103, PM.— Oblique 

 depressa, subangulata, subtus albida, superne castanea aut 

 flavida, spira depresso-conica, callo rotundo tumido, umbi- 

 licum replenti, ad suturam tumido. — Of a depressed, rather 

 angular form, with a large callus at the suture, sometimes 

 showing above the edge of the outer lip, and an umbilical 

 callus completely filling up the wide cavity. 



11. CLAVATA, f. 27, 167, Sowerhy. — Oblique ovata, 

 albida ; umbilico magno, profundo, callo umbilicali magno 

 claviformi, rotundo, planato interne spiraliter continuo. — 

 Differing from N. Incei in the more obliquely oval form, 

 and in having the button-shaped umbilical callus separated 

 from the body-whorl so as to show its spiral origin in the 

 cavity. 



12. Draparnaudi, f. 84, i2ec^ii0, — Globoso-subacuminata, 

 obliqua, anfractibus declivibus, anfractibus aurantiis, ad 



