184 
berculis albis, connatis, ad angulum acute carinatis ; anfractu 
ultimo inferne nodulorum seriebus plurimis cingulato. 
Conch. Icon., Plewrotoma, pl. 12. f. 107. 
Hab. ? 
Chiefly distinguished by the white turreted keel. 
Prevrotoma Puruipprinensis. Pleur. testdé ovato-turritd, ventri- 
cosd, subpellucidd, albidd ; anfractibus sex septemve, longitudina- 
liter costatis, costis eximiis, subcompressis, subdistantibus, nigro 
aut fusco alboque varie pictd; transversim liratis, liris minutis, 
subcontiguis, numerosis ; columelld subtortuosd ; aperturd ovatd, 
ampld ; canali brevissimo. 
Conch. Icon., Pleurotoma, pl. 13. f. 109. 
Hab. Islands of Masbate and Luzon, Philippines (found under 
stones at low water) ; Cuming. 
It is impossible to do justice, either by figure or description, to 
this very delicate and beautiful species, the chief peculiarity of which 
is the black and opaque white irregularly-variegated blotching of the 
ribs. Several specimens were collected by Mr. Cuming at the above- 
mentioned islands, varying more or less in the number and proximity 
of their ribs: one or two specimens have as many as sixteen ribs on 
the last whorl,—twelve to fourteen is the average number. 
Purvroroma Rissorpes. Pleur. testd elongato-ovali, levi, nitente, 
semipellucidd, albicante, fulvo pallidissime nebulosé strigatd ; an- 
Fractibus septem, tribus longitudinaliter plicatis ; apice rubello ; 
columelld spiraliter tortuosd; canali brevissimo, leviter recurvo ; 
labro subincrassato, intiis eximie denticulato, sinu parvo, distincto. 
Conch. Icon., Pleurotoma, pl. 18. f. 111. 
Hab. fs 
This species reminds me somewhat of the Rissva deformis ; the first 
whorl or two are plaited as in that shell, the surface is moreover 
smooth and shining, and they bear a general resemblance to each 
other in size. The apex of this shell is peculiar in being pink, whilst 
there is not the least indication of that colour in any other part. 
Prevrotoma Bonouensis. Pleur. testd subelongatd, tenui, sub- 
pellucidd, albidd, fulvo subindistincté virgatd ; anfractibus octo, 
transversim lineatis et liratis, striis quoque subtilissime reticulatis ; 
columella spiraliter tortuosd ; canali brevissimo, paululiim recurvo ; 
labro simplici, acuto, sinu parvo. 
Conch. Icon., Pleurotoma, pl. 13. f. 112. 
Hab. Island of Bohol, Philippines (found under stones on the reefs 
at low water) ; Cuming. 
This shell, which is of a much thinner and slighter composition 
than either of the two preceding ones, is very finely reticulated over 
with strie; and it has a number of lines and ridges running trans- 
versely across the whorls, but none longitudinally. 
PLevROTOMA GRACILENTA. Pleur. testd gracillime fusiformi, fulvd, 
anfractibus convexis, longitudinaliter costellatis, costellis leviter 
nodulosis, striis elevatiusculis transversis decussatis ; labro sub- 
flewuoso, sinu lato ; canali breviusculo. 
