226 Zoological Society. 



ScissuRELLA DECUSSATA, D'Otbigny. 



Scissurella decussata, D' 0;-6i^«y, M^m. Soc. (THiat. Nat. de Par. i. 

 p. 340. 



Scissurella crispata, Fleming. 



Scissurella crispata, Fleming, Brit. An. p. 361-366. 



Monograph of the Genus Anatinella. 

 By Arthur Adams, R.N., F.L.S. etc. 



Anatinella, Sowerby. 



Shell ovate equivalve, nearly equilateral, anterior side rounded, 

 posterior slightly beaked and subtruncated. Ligament internal, fixed 

 to a spoonshaped process in each valve, on the anterior side of which 

 are placed two rather elongated cardinal teeth. Muscular impres- 

 sions two, lateral, distant, the anterior oblong and irregular, the poste- 

 rior nearly circular. Palleal impression entire, without any sinus. 

 No testaceous appendage withm the hinge. 



Anatinella Sibbaldii, Sowerby. A. testd solicliori, subopacd, 

 Icevi, valde concentrice corrugatd, longitudinaliter obsolete suh- 

 striatd ; latere postico, acuminata, subtruncato ; margine dor- 

 salt postice declivi ; processu cochleariformi crasso lato ; mar- 

 gine ventrali valde arcuato. 



Hab. Ceylon, on the sands. (Mus. Cuming.) 



Anatinella dilatata, Adams. A. testd teniii, fragili, concen- 

 trice corrugatd, longitudinaliter striata, latere postico dilatato, 

 oblique valdk truncato, margine dorsali postice horizontali recto, 

 pj'ocessu cochleariformi parvo tenui, dentibus cardinalibus valdi 

 divergentibus ; margine ventrali arcuato. 



Hab. Puteao, Philippines, on sand-banks, at low water; H. C. 

 (Mus. Cuming.) 



Anatinella ventricosa, Adams. A. testd tenui, ventricosd, 

 semipellucidd, concentrice corrugatd, longitudinaliter conspicud 

 striatd, striis elevatiuscidis, latere postico rotundato ; margine 

 dorsali postice declivi ; processu cochleariformi tenui, angusto ; 

 margine ventrali leviter arcuato. 

 Hab. Puteao, Philippines, on sand-banks, at low water; U.C. 

 (Mus. "Cuming.) 



February 26.— W. Spence, Esq., F.R.S., in the Chair. 

 The following paper was read : — 



Monographs of Cyclostrema, Marryat, and Separatista, 

 Gray ; two genera of Gasteropodous Mollusks. By 

 Arthur Adams, R.N., F.L.S. etc. 



Cyclostrema, Marryat. 



Animal ignotum. Operculum — — .'' Testa depressa, perspectivo- 

 umbilicata ; apertura circularis. 



Cyclostrema cancellata, Marryat. C. testd albd, lineis lon- 

 gitudinalibus et transrersis elevatis decussatitibus inde cancel- 



