D L I U M . 



Species i. (Mus. Bnt.) 



DoLlu.M JiELANOSTOMA. I)ol. testd mbgloboso-turbinatd, 

 miibiUcatd, ventricos'mma, spird mbprombmld, anfrac- 

 tibiis srpfviii. fraiisversim. costatis, costis subdepresso- 

 coi/ri'.ni. iii/rz-ififiis Ufa parvd -subsidente undiqiie 

 iiiijili'lis. i-()hi],idld late expansd, nperlurd ampld, bast 

 subprofimdi Litiarginatd ; hitmci'iiti'-iiVi'iihi. la'v'ujdlM, 

 iiiteiiti;, cohmielld interne iiiijni'iiiili--liri'iiiii'd. 



TiiK BLACK-MOUTH TuN. Shell souicwluit globoseK 

 turbinated, umbilicated, veiy ventricose, spire rather 

 promiueut, whorls seven in number, transversely 

 ribbed, ribs somewhat depressly convex, interstices 

 filled throughout with a small ridge, columella widely 

 expanded, aperture large, rather deeply eraarginated 

 at the base ; yellowish white, smooth, shining, colu- 

 mella deep blackish brown. 



Jay, Cat. Mus. p. 124. pi. 8-9. 



Hab. Friendly Islands ; Jay. 



The shell here represented, from the Britisli Museum, 



lieloiiged to the lale Earl ol' Tankerville, and is the indi- 

 vidual specimen noted by Mr. Sowerby iu his well-known 

 Catalogue of that nobleman's collection, as Dolium galea 

 var. d. 1 believe it to be distinct ft-om that species, which 

 is an inhabitant of the Mediterranean, and to be identical 

 with a shell from the Friendly Islands in the collection of 

 Dr. Jay of New York, described by that gentleman, under 

 the name above recorded, iu his published ' Catalogue ' of 

 1839. " This splendid shell," says Dr. Jay, " was brought 

 to Nantucket by a whaler from the Friendly Islands, 

 where it was obtained by tlie natives in diving for shells." 

 The D. iiielanostoma is chieily distinguished from the 

 D. galea in having a more prominent spire and a regularly 

 developed ridge throughout the interstices between the 

 ribs, which have a lighter and more polished surface. 

 The base of the shell beneath the umbilicus is characterized 

 by its numerous concentric stria-, whilst in the D. galea it 

 is ridged in a longitudinal direction ; and the rich dark 

 colouring of the columellar lip appears also to be a cha- 

 racter of the species. 



December. Is48. 



