TURRICULA SENTICOSA. _T._ reflexo-emarginata, costis reticulatis. d'Arg. Conch. t. 12. f. O. Testa gibba, costis sæpius 12 perpendiculari-obliquis, intertextis striis lamellosis transversis ad anastomosases muricatis, unde admodum scabra evadit. Anfractus ventricosi, sæpius x. Color griseus. Apertura ovata, interne striata, emarginata, parum reflexa. Evidently this was identical with the _M. senticosus_ of the 'Systema.' M. OLEAGINEUS. _M._ angulis sulcis inæqualibus, labio interiore rugoso, costis alternis. Gualt. Test. t. 49. f. G. d'Arg. Conch. t. 13. f. M. Habitus et structura _rubeculæ_, at octies major, nec vivide pictus, sed colore testaceo fasciis fuscis longitudinalibus. Apertura intus saturate crocea, rugis albis. Apparently this was the _Triton pileare_ of authors,--not the Mediterranean shell (_T. corrugatus_) termed _M. pileare_ in the 'Systema.' M. PILEUS HELVETICUS. _M._ angulis rotundatis, tuberculis conicis, apertura utrinque canaliculata. d'Arg. Conch, t. 12. f. D. Rumph. t. 28. f. D. Testa ovata, admodum inæqualis, adspersa nodis conicis tuberculatis inæqualibus. Costæ latere antico membranaceæ, primæ 2 oppositæ, reliquæ alternæ. Color flavus. Apertura hians, antice et postice canaliculatæ, faux intus striata. Labium exterius dentatum, intus dilatato-membranaceum. This suits very fairly the _Triton lampas_ of authors; far better, indeed, than does the _M. Lampas_ of the 'Museum Ulricæ.' M. SUBULATUS. _M._ ecaudatus, pyramidalis. Testa subulata instar turris, anfractuum undecim, reticulata striis elevatis decussantibus punctis contiguationem eminentibus. Costæ oppositæ et alternæ. Color albus, maculis flavescentibus. Apertura ovata, Labium exterius crassum, intus dentatum. Interius dentato-glabrum. Both _Triton! maculosus_ and _Ranella candisata_ approach the ideal portrait, yet neither of them precisely agrees. Under the name of _Trochus turritus_ our author appears to have first described his _Murex radula_. _Trochus_ exumbilicatus, pyramidatus, anfractibus duplici serie muricatis. Gualt, t. 58. f. F. Testa elongata, flavescens s. testacea. Anfractus 16, connexi sutura crenulata, dorso duplici serie instructi punctis eminentibus pallidis. Apertura subtetragona, subtus in canalis rudimentum desineus. The _Murex Neritoideus_ of the 'Systema' was thus described. LYRA NERITOIDES. _L._ testa nodosa subrotunda. Gualt. Testa crassa, ponderosa, alba cum rubedine tincta, figura Neritæ, magnitudine juglandis, cincta anfractibus 5 e nodis obtusis crassiusculis. Labium interius depressum, longitudine pictum macula ferruginea. TROCHUS. Testa conica. Apertura quadrangularis, basi columella contorta, sinu descendens. The last five words had been substituted for "absque sinu evidente." T. MACULATUS. _T._ contorto-umbilicatus conicus, vertice subnodoso.