56 CALYTIUMDM. 



margine crenato. — This species has the strise more regularly 

 and deeply cut than in any of the allied species. It has 

 a crenulated edge, and forms a shelly plate, which is also 

 crenulated at tlie margin. Lamarck having selected this out 

 of several species which may have been intended by Linnoeus, 

 it has been so accepted by conchologists. 



2. ciCATrJCOSA, f. 3, 4, 35, 36, Reeve. — Tenuis, depressa, 

 tenuissime striata, annulis concentricis undulatis rugata. — 

 Thin, finely striated, roughened with concentric swellings, and 

 having the apex nearly central. Adamsii, f. 4, and Cyathella, 

 f. 35, appear to be really undistinguishable from this, although 

 the former has been found with a shelly base as in equestris. 



3. DOEMiTORiA, f. 19, 20, 53, Reeve. — T. solidiuscula, ven- 

 tricosa, tenuiter striata, apice valde arcuatim retrorso, acuto. 

 Eather solid, ventricose, finely striated, with apex arched in 

 a backward direction. 



4. STULTORUM, f. 29,Reeve. — Oblique conica, dense striata; 

 apice acuto producto curvo. — Obliquely conical, very closely 

 ribbed, with the arched acute apex leaning beyond the 

 margin. 



5. UNCINATA, f. 28, Reeve. — Subdepressa Isevis ; apice 

 uncinato retrorso. — A smooth round species with a hooked 

 and much recurved apex. 



6. SACCHARi-META, f. 8, 9, Reeve. — Eotunda elevata Isevius- 

 cula, apice subretrorso.— This very elevated, rounded shell 

 has very little sculpture of its own, the waved lines and 

 crenated margin of the specimen resulting from inequalities 

 in the surface of attachment. 



7. TONGANA, f. 38, 39, Qiioy. — Parva subrotunda ven- 

 tricosa Igevis apice rotundo marginali. — Small, rather round, 

 ventricose, with the apex round, marginal. 



8. BULLA, f. 18, Reeve. — Tenuissima subinflata laminam 

 tenuissimam basalem formans ; rugis concentricis et striis 

 rauiantibus regulariter insequalibus cancellata. — This species 

 sometimes forms a basal plate. The sculpture is extremely 

 fine, but, when magnified, shows equi-distant radiating 

 ridges with fine striae delicately cancellated between. 



9. CEPACEA, f. 7, 5, 6, 35, 36, Broderip. — Tenuis planulata 

 expansa orbjculata tenuissime striata, apice acuto, retrorso. 



