D L A B E L L A . 



Genus DOLABELLA, Lamarck. 



'lata manna, quain corpua mum miiUu ui'mor, suh paUio 

 ccnlata, calcarea, sitbspiralis, aperta, expanm, dolabr'i- 

 formh, ad dorsuiii epidermkle cornea, tenui, iiik'nti iii- 

 diitri, ad. apieeni cullo subspirati, super muryines coii- 

 tiiDiii ft reflexo incrassata. 



.Slii'll marine, murli smaller than its body, concealed under 

 the mantle, calcareous, subspiral, open, expanded, 

 liatchct-shaped, covered on the back with a horny, 

 thin, shining epidermis, thickened at the apex with a 

 subspii'al callus, continued and reflected on the mar- 

 gins. 



The DolabeUa' iliffer little from the .Ipbjsi/t, except- 

 ing in the calcareous structure of their shell, which, like 

 that of Lintax, is concealed under the mantle, and is small 

 as compared with the entire body. The apex of the shell 

 is more spiral than in Jplpia, and its thick, half-spiral 

 callus is remarkable. The Dolabrifera are similar ani- 

 mals, having very small shells without any spiral tendency. 



The habitats of the few known species are New Hol- 

 land, Society Islands, the Indian and Red Seas. 



Species 1. (Fig. a, b, Mus. ]^rit.) 

 I)oi,\liEI,LA GIGAS. Bol. teatil maynd, obhnrjd, comexu, 



unlici rotuudalu, conceidrke eler/anter nigatd ; eallo 



periiwijno, edpanso, i/itiis excavalo, marrjine tenui; 



marijhii' terminaVt rotniido. 

 Till! GIANT DoLAJiELLA. Shell large, oblong, convex, 



rounded in front, concentrically elegantly nTinkled ; 



callus very large, expanded, excavated within, with 



thin edge ; terminal margin rounded. 

 Rang (Ap/j/.sia), Hist. Nat. Aplys. p. 48. pi. o. f. 4. 

 Hab. Indian Seas. 



In Mr. Cuming's collection there are two specimens 

 with expanded, cyathiform calli, which I take to be the 

 young of this species. They are marked " Red Sea." 



Species 2. (Fig. a. b, Mus. Brit.) 



DoLABELLA fiLONGAT.v. JJu/. fesid obloiiijd, arcuald, 



ralde atlenuatd, iidus conccntrici leviter rmjald, ru- 



diuthii subplicata, callo spiraUter pllcato, tmaklo, 



■super dorsum late expauso, super margines tale usijue 



,i„Ii 



nint; ; 



ad terminum reflexo; luaryiti 

 eplderuiide fasco-subanranlid. 

 The elongated Dolabella. Shell oliiong, arched, 

 much attenuated, concentrically slightly wrinkled 

 within, radiatcly subplicated, callus spirally plicated, 

 tumid, widely expanded over the back, widely re- 

 flected upon the margins as far as the end ; terminal 

 margin angular, epidermis brown tending to orange. 



SoWERiiY. 



Hub. Seychelles. 



It is barely possible that this may be a monstrous ex- 

 ample of Dolabella RumpJuL tt presents, however, an 

 appearance so extremely diHerent, that it would hardly be 

 just to leave it without a name. 



October, ISOS. 



