
EZ, 
167 
Diagnosis.—From G. strigosa, A. Adams. 10 is smaller, 
comparatively narrower, the spire is terminal, the aperture is 
more oblong, the columella is straighter, the outer lip joins 
the columella almost at a right angle. A juvenile G. strigosa, 
equal in size to an adult G. terminalis, has been drawn in 
Plate xxxi., fig. 6, for comparison. 
It very closely resembles Gena nigra, Quoy & Gaimard, 
Voy. de l’Astrolabe, Zool., Vol. iii., p. 307, Plate Ixvi. (bis), 
figs. 10, 11, 12; but their species, as figured, has its spire less 
terminal, and rests more upon its two ends, and, according to 
the dimensions given, is three times as large. 
—— 
f 
} 
calliston, spec. nov. Pl xxxi., figs. 7, 8. 33. 
Shell conical, thin. Spire of nine whorls, including two 
smooth apical turns; gradated. Whorls straight-sloping, 
with crowded spiral lire, about 24 on the penultimate ; cross- 
ed by oblique crowded accremental strie, producing sub- 
lenticular pitting. Suture linear, immediately beneath the 
prominent peripheral cord which gradates the spire. Body 
whorl with suture slightly descending at the aperture; spiral 
threadlets about 24 ; crowded fine sinuous oblique accremental 
strie; periphery acutely angular, with a projecting round- 
ed carina, spirally closely engraved on its upper surface, axi- 
ally crossed by rounded striz, much more distant than the — 
accremental stria, provided at somewhat irregular intervals 
with 16 rounded invalid tubercles. Base very flatly rounded 
with 7 concentric narrow lire, the inner 4 closer than the 
rest, which are separated by 4 to 6 inter-lirate strie. Umbili- 
cus narrow, minutely axially incised. Aperture oblique, 
roundly. quadrate; outer lip slightly convex, thin, smooth 
within, margin sinuously convex below the suture, concave 
towards the periphery; basal lip convex, slightly effuse, 
smooth within. Columella, upper third concave, the rest 
straight, obliquely truncate below; callus at the base partly 
bordering the umbilicus and attached to the columella along 
a vertical groove. 
Ornament.—Shell purple-brown, with somewhat oblique, 
axial, creamy, rhomboidal flames, extending from suture to 
suture, and nearly equalling the foundation colour in area. 
On the peripheral carina, and hence above the sutures, they 
are replaced by two or three creamy spots, while two or three 
less marked white spots o-cupy the intervals, and thus pick 
out the tubercles of the carina. Every whorl is encircled by 
four articulated colour bands, which in the white areas are 
of a more opaque white than the rest of these areas, and ex- 
tend slightly beyond them, and are crossed by narrow verti- 
cal or oblique red lines, while in the purple areas they are of 

