GASTEROPODA. 257 
sharp, anteriorly sulcated, the depressed portions dark livid, except 
near the edge; pillar lip strongly arcuated at its central portion, having 
a distinct, revolving lamina posteriorly, and elongated granules ante- 
riorly ; siphonal notch deep, narrow, oblique ; anterior portion of the 
pillar-lip well covered with appressed, rounded callus. 
Length four-fifths of an inch; breadth nine-twentieths of an inch. 
Inhabits the Cape de Verd Islands. 
This is one of the most beautiful species of the genus, and is well 
characterized by its polished surface, and its clouding of white and 
olive, made up of little quadrate spots, arranged in encircling series 
resembling mosaic. It may be B. pictum, Dunker. 
Figures 324, 3244, two views of the shell. 
Nassa Luripa (Gould). 
Testa solida, conico-ovata, levis, livido-cinerea allndo-variegata: spira 
conica, acuta, turrita, anfractibus septem ad octo convexiuscults, 
superné tabulatis et ad angulum crenato-nodosis, apicalibus plicatts, 
ultimo antice suleis tribus ad quatuor cincto et pone labrum plicato ; 
suturad canaliculata: apertura dimidiam longitudinis teste, ovals, 
postice emarginata ; columella posticé lamellifera, anticée dentiferd ; 
labro acuto, albo, extus incrassato, intus sulcato ; canal stphonalt pro- 
Sundo. 
Nassa lurida, Goutp; Proceed. Boston Soc. Nat. Hist., il, NSS} 
January 1850. Expedition Shells, 68. 
SHELL solid, ovate-turreted, smooth, and shining, the upper whorls 
longitudinally plaited and somewhat crenulate at the posterior margins, 
or rather nodulous on the larger whorls, also with four or five acute 
folds behind the lip, and about three or four revolving grooves around 
the siphonal notch. Colour greenish-ash, finely freckled with white, 
the nodules white and the spaces between them darker, sometimes 
decidedly blackish ; approaching the lip it gradually becomes white, as 
does also the siphonal region. Whorls seven or eight, distinctly shoul- 
65 
