80 TESTACEOUS MOLLUSCA. 
230.?—Z. t. 262. f. 6. (Worn shell. T. Purpurascens. G'mel. 
323.—W. t. 4. f. 49.) Triangular, wedge-shaped, anteriorly de- 
pressed, and somewhat wrinkled transversely; most minutely 
striated longitudinally, tawny flesh colour with dull lilac zones: 
angle at the beaks sharp; margins angulated: anterior slope 
totally destitute of longitudinal strie. 11..13.—Sumatra. 
D. Detroiwes. Lam. 5.—An. Son. G. ?-- Reeve. t. 60. f. 4.7 
Triangular, pink, and nearly smooth, the anterior slope flattish and 
longitudinally striated. A angaroo Island.—Larger and less com- 
pressed than the last. 
D. Fana. Chem. f. 267.—D. p. 155.—W. t. 6. f. 16.—D. 
Rapians. Lam. 6.—. t. 261. f. 7. Oval, convex, finely 
striated transversely, the anterior slope obliquely wrinkled, white 
rayed with fulvous but variable in colour.—Variety. Not rayed 
but spotted.—Ch. f. 266. $..— Malabar. 
D. Assreviata. Lam. 7. Triangular, proportionably less 
broad than the other species, very delicately striated transversely, 
polished white with two red and a bluish ray, anterior slope with 
ragged wrinkles ; ventral margin quite entire and arcuated. 1}. 
D.CotumBetia. Lam. 9.—Del. t. 6. f. 1. Ovate, cuneiform, 
polished with radiating anastomosing lines, very pale violet with 
indistinct zones: anterior side short and obliquely truncated, the 
slope with crowded and transverse strie.— Variety. With the 
zones and interior violet.— Variety. White. 3..1.— New 
Holland. 
D. Venertrormis. Zam. 10. Roundish, triangular, trans- 
versely striated, grey with indistinct rays: anterior slope with cre- 
nulated striz. 151,.— Asiatic Ocean. 
D. Austrauis. Lam. 11.—Ast. t. 81. f. 20, 1, 2.—D. Os- 
scuRA. Desh. E. t. 2. p. 98. Ovate-triangular, transversely 
striated, whitish or fulvous: violet within; anterior slope decus- 
sated and sub-granular. 11.— New Holland and Timor.—Not 
unlike Bicolor. 
D. Epipermia. Lam. 12. Triangular, wedge-shaped, nearly 
smooth ; anterior end obtuse, and the slope longitudinally striated : 
epidermis yellowish green. — New Holland.— Not unlike Capsa 
Levigata, but differing by its hinge, and the being more wedge- 
shaped.1 

1] have not seen an authenticated specimen of this species, but 
the shell figured as Deltoides by Sowerby (Sow. G. f. 4.) and 
Reeve (¢. 60. f. 4.) agrees better with this brief description, than 
with the equally concise characteristics of that species. The follow- 
ing description is taken from a specimen named by Mr. Sowerby 
himself. Triangular, sub-cuneiform, glossy, orange yellow under a 
very thin olive epidermis, posteriorly attenuated obtuse, much com- 
S 
