Monograph on the Cyprceidew, by Mr. Gray. 71 



tare acute above, regularly rounded at the base, and extending 

 from the centre of the revolutions or base of the column, to an 

 equidistance between the base and apex of the spire, base of the 

 columella slightly projecting into an obtuse angle, exterior lip 

 whitish, reflected, length \ of an inch. 



" Animal pale, rostrum and tentacula blackish, operculum 

 simple, not spiral, yellowish brown, minutely granulated." 



Oligyra orbiculata. Say Jour. Acad. Nat. Sci. p. 283. Amer. 

 Conch. 



East Florida. Say. 



Helicina striata. 



Testa depresso-ovata, tenuis, subpellucida, oblique striata, albi- 

 da; columella lutescente, labro margine subreflexo. Lamarck 

 Hist. vi. 103. 



Porto Rico. Mauge. Diameter five lines. 



Akt. XI. .Monograph on the Cyprccidece, a Family of 

 Testaceous Mollusca; by Mr. John Edwaud Giiay. 



CYPB/EinByE. 



Concha. Martial. Concharum Veneris pars, Lister Conch. Por- 

 ccllana. Gualtier. Martini. 



Cypraearum et Bullarum pars, Linn. Partie des Euccinoides, 

 Cuvier. Partie des Sipbonobranches, Dumeril. Goldfuss. Par- 

 tie des enroulees, Lamarck. Partie des apomastomes enroulees, 

 Ferussac. Angyostomes involves, Bluinville. 



Cuar.dif. Animal, unistxuale, capite et disco distinctis. Ten- 

 taculis duobus conico-suhulatis, oculis sessilibus ; branchiis pec- 

 tinatis, pallio margine reflexo ; operculo nullo. Testa non sym- 

 metrica subinvolutsl demum corticata. Apertura elongata, liueari 

 extremitate utraque canaliculata. 



Animal unisexual, head distinct, tentacula two, conical, awl- 

 shaped, eyes two, sessile, at the external angle of the base of the 

 tentacula. 



Respiratory cavity open, o*er the back of the neck: gdls in a 



