85 
terior extremity. Color greyish-white. Reddish-brown inside 
from suture to shoulder, indistinctly visible outside in the intey- 
stices of the crenulations. Operculum horny, nucleus apical, 
anterior. 
Length, 15 mm.; breadth between the varices, 7'5—including 
them, 9-5. Length of aperture, 5; breadth, 3; of canal, 6; of 
spire, 4mm. One broken shell has an aperture of 5:5 mm. long, 
and a canal of 8 mm. 
No Murex known to me so resembles it as to require a dia- 
gnosis. ; 
Habitat.—Backstairs Passage, S.A. Dredged in 20 fathoms, 
one alive; 17 fathoms, one alive immature; 22 fathoms, one 
recent ; ? depth, seven dead, three recent (J. C. Verco). 
Type specimen in my collection. I have named it after the 
well-known. President of the Royal Society. 
Murex (Poropteron,. Jouss ane; Bay) robustus, spec. nov. Pl. ii., 
: igs. 3, 3a. 
Shell ovate trigonal, solid, spire not quite so long as body 
whorl. Whorls six, exclusive of nucleus. Nucleus slightly 
papillate one and a-half turns, dextral. Spire-whorls subconvex, 
nearly smooth. Sutures distinct, simple. Varices three, regular, 
almost continuous, each just behind that on the previous whorl, 
and ending posteriorly in a sinuous, stout, roundly-trigonal tube, 
directed towards the apex of the shell. On the left side of the 
varices are short, stout, spiral buttresses, three on the penulti- 
mate, from the lower suture to the base of the tube behind. 
Body-whorl convex, scarcely shouldered above. Varices..three, 
low and stout, ending close to the suture in a tube, trigonal in 
section, stout and sinuous, like a horn, extending backwards, 
hollow, rugose, and showing the scar of closure, just to the left 
of the anterior edge. Surface of whorl rather rugged, with five 
or six obsolete spiral lire, and sublenticular very fine, incised, 
longitudinal growth-lines. Aperture oval, slightly oblique, small, 
entire ; peristome projecting as a thin, detached, simple, sharp ° 
lamina, from + to 4mm. On the outside of the outer lip are 
six rounded, tubular, spiral ribs, extending to the margin of. the 
yarix (forming the “buttresses” of the varices on the spire) ; 
she most anterior is very short, and ends in the scar of the canal, | 
‘Columella invisible. Canal completely closed ; length just longer 
than the aperture ; at its anterior end bent at a right angle, and 
then curved slightly to the right, with a capillary opening from a 
little behind the bend to the extremity, numerous fine, incised, 
longitudinal sinuous lines on its basal aspect. Labial varix saw- _ 
like, with nine forward-curved, claw-like processes; the central 
ones terminate the obsolete spiral lire of the whorl, and from — 
