74 



This very beautiful species displays considerable variatibn in the 

 character of its markings. In some individuals the exterior is nearly 

 vvhite, \vith a fe\v scattered transverse lines, composed of elegant 

 minute dottings, and these are perhaps the older shells ; from this 

 they gradually become more and raore covered with them, till in some 

 the whole surface is ąuite darkened. In this latter case irregular 

 lines become conspicuous in the longitudinal direction. In many 

 specimens the transverse lines are separated by intervals, \vhich per- 

 mit the ground-colour of the shell to sho\v through likę milk-white 

 bands. The outer lip seems in all cases to retain its uniform white 

 colour, and at its upper part is slightly emarginate, but becomes 

 thickened at and a little beneath the centre. 



Margixella sapotilla. Mar. testd elongate ovatd, /ere subcy- 

 lindraceo-ovatd ; vinered vel glaucescente, concolore ; spird retuso- 

 conicd ; aperturd intus fuscd ; lahro incrassato, recto, albo, postice 

 fvlvo, intiis lavi ; columelld guadrip/icatd. Axis 11 lin. 

 Hab. Panama ; in from five to thirteen fathoms, sandy mud. 

 Cab. Belcher et Cuming. 



The American analogue of M. ccerulescens, or more correctly M. 

 prunuin, than •ft'hich it is of smaUer size, more cyliiidncal in shape, 

 vv'hence result its straight outer lij), less fullness and roundness of the 

 shoulders, but without any disposition to.that obscure banding which 

 is visible in some specimens of M.primum. Both species present a 

 vich bro\vn colour within the aperture, and in general appearance 

 they are remarkably alike. 



Marginella coNSTRicrA. Mar. testd albidd, obscure trifasciatd ; 

 spird retiise conicd ; anfractu ultimo prope medium coarctato ; labro 

 incrassato, medio i/iciirvato, intits Icevi, siipenie ad spiram adscen- 

 dente ; columelld guadriplicatd. Axis S lin. 



Hab. ? 



Cab. Cuming. 



Marginella nivosa. ^far. testu ovatd, cinereo-fuscd ; maculis 

 lacteis Inceratis siiper lineas longitudinales dispositis ; spird retusd ; 

 labro siibrecto, incrassato, albo, ad spiram adscendenle, intus infra 

 medium Iceviter denticttlato ; columelld quadriplicatd. Axis 9 lin. 



Hab. ? 



Cab. Cuming. 



A fuU-shaped oval shell of a fa\vu colour, with longitudinal lines, 

 as if marking the periods of growth, on which are aggregated small 

 irregular milk-\vhite spots ; these are generallj' clustered on the lines, 

 but a fe\v occupy the intervals between them. The outer lip is of 

 an uniform white, and beneath its middle are a few rather indistinct 

 denticulations ; above it ascends to the spire, %vhich it renders cal- 

 lous on that side. \Vithin it is of a pale fawn-colour. 



Marginella pruinosa. Mar. testd ovatd, coarctatd, albidd, obso- 

 lete trifasciatd, maculis parvis lacteis conspersd ; spird conico- 

 retusd, subcallosd ; lahro incrassato, pauhUim incurvato, intis 



