TRIBE MACTRACEA. 43 
strie; hinge with a single erect tooth in each valve, and a 
corresponding pit for its reception. }..1.—Hngland, &c. 
A. Purpurascens. Lam. 14. Oval, thin, rather small, with 
obsolete transverse striz, purplish white.— Cherbourg.® 
A. Nucteota. Lam. 15. Minute, rounded, inequilateral, 
convex, whitish tinged with scarlet. 1.—Cherbourg.® 
A. Paysorpes. Lam. 16. Orbicular-globose, hyaline, vesicu- 
lar, size of a pea.— King George’s Port.t 
A. Decussatum. Gray. Ann. Phil. 25.—Tetuina D. Wood 
G. C. t. 43. f. 2,3.—D. p.97.—W.t. 2. f. 17. Sub-orbicular, 
rounded at both but rather produced at one end, with very fine 
decussated striae, white with the beaks rosy and the inside marked 
with reddish, purplish, or brownish zigzag lines which do not extend 
to the margin. 1..14. 
A. Sotipum. Gray. Spic. Z. t. 6. f. 6. Thick, solid, sub- 
orbicular, with concentric grooves, and delicate radiating striz, 
anteriorly somewhat wrinkled; hinge margin purple ; lunule minute, 
lanceolate : cardinal teeth very thin. 23.—Peru. 
A. Corvirorme. Gray. Ann. Phil. 25.—Trtima C. D. 
p- 97.—Ch. f. 1941, 2.—W. t. 4. f. 82. Sub-orbicular, whitish, 
strong, convex, densely striated longitudinally, and finely trans- 
versely : within stained with rich yellow, and the hinge cen- 
tral. 14..12. 
5 Probably this is the Ervizia nitens.* Turt. Biv. t. 19. 
f.4.—Mya H, Mont.—D. p. 47. Oval, flattish, inequilateral, 
pinkish, finely striated transversely, rounded at both ends: a strong 
erect cloven tooth in one valve, closing into a deep cleft between two 
small laminar divergent elevations in the other. ..4.—Hngland. 
6 Probably the Kexu1a Rusra.* Turt. Biv. t. 11. f. 7, 8.— 
Carpium R. Mont. t. 27. f. 4.--D. p. 131—Tewiina R. 
Turt. D.—Bornia Seminutum. Philippi. p. 14. t. 1. f. 16. 
(fide Forbes.) Minute, oval, very inequilateral, rounded at the 
sides, smooth or finely shagreened, reddish under a green or brown 
epidermis : inside glossy purple ; hinge with two approximate car- 
dinal teeth in one valve, a concave one in the other, a lateral tooth 
ineach. 1—EHngland. 
7 I should not be surprised, if in spite of the locality, this may 
prove identical with the Kern1a Susorericuraris.* Turt. Biv. 
t.11.f.5.6.—Mya S. Mont. t. 26. f.6.—D. p. 55.—W. t. 3. 
f. 37.—-Bornia Ineuara. Philippi. p. 14.—An. Erycrna 
Greorrroyi. Payr.t. 1. f. 3, 4,5. p.30? Small, rounded oval, 
very convex, yellowish white, nearly smooth, equilateral, rounded 
on both sides, yellowish white: beaks prominent: teeth of K. 
Rubra. 4..¢—Lngland. 
