22 TESTACEOUS MOLLUSCA. 
rior end shortened, thin, smooth, white, transparent, with an ante- 
rior rib : hinge with a narrow tooth which is united to the margin. 
12,— New Holland. 

equilateral, inzequivalve, depressed, transversely plaited, smooth, 
white, thin, polished, posteriorly rounded, anteriorly obliquely 
truncated, somewhat compressed. 13. 
T. Puaseouina.* Kiener, 2. f.4.—AmpuipvesMma P. Lam. 11. 
—Mya Decurivis. Mont. t. 1. f. 2.—Wood. G. C. t. 18. f. 3. 
—Awnatina D. Turt. B. p. 47. Ovate-oblong, transverse, subde- 
pressed, subzequilateral, inequivalve, white, subdiaphanous, finely 
striated transversely, anteriorly shorter, angulated and truncated. 
1..3.—Mediterranean, §e. 
T. Sruinis. Couthouy in Boston Journ. 1839. p. 150. t. 4. f. 3. 
Ovate-oblong, rough with minute granules, whitish, or ash colour, 
semitransparent, inequilateral, anteriorly much longer attenuated, 
truncated and subeompressed ; ventral margin little rounded, not at 
all sinuated ; within white, not glossy, hinge with a subtriangular 
hollow ; external ligament small and slightly prominent : beaks not 
prominent. 141,— Brazil. : 
T. Conran. Couthouy, in Boston Jour. of N. H. 1839. t. 4. 
J. 2.—T. Decurvis. Conr. Am. Conch. t 9.f. 2.— Gould. Mas. p. 
50. Transversely ovate, ashy white, not shagreened, ventricose, 
subzequilateral, fragile, little gaping, margin much sinuated, anteriorly 
longer, subtruncated, posteriorly rounded, the beaks prominent, the 
anterior slope obtusely keeled. 2,°,.—New England. 
T. Convexa.* Couthouy in Bost. J. of N. H.1839.—Mya C. 
Wood. G. t. 18. f. 1.—W. t. 2. f.3.—Anatina C. Turt. B. t. 4. 
Ff 1, 2. Obovate, posteriorly broad and rounded, anteriorly atte- 
nuated, obliquely truncated, longer, with an obtuse ridge from the 
protuberant umbones, to the ventral margin, which as well as the 
anterior is sinuated ; very convex, thin, white under an ochreous 
epidermis, with numerous strize of growth: inside yellowish. 13..2. 
—Fingland. 
T. Corputorpes. Desh. in Lam. 7. p. 83.—Kiener Thracia. 
t. 2. f. 3.— Bl. t. 76. f. 7.—Reeve. t. 35. f. 3. Transversely ovate- 
oblong, inequilateral, greyish-white, minutely shagreened, very 
inequivalve, with irregular concentric strie, anterior side the longer 
and attenuated, posteriorly obtusely rounded ; beaks large, ventral 
margin with a prominent outward curve in the centre : within milk- 
white, glossy. 13. .24— Mediterranean. 
T. Curra. Conr. Jour. A. N.S. Phil. 7. p. 248. t. 19. f. 8. 
Suboval, inequilateral, posteriorly obtusely rounded and shorter, 
anterior margin direct, subrectilinear, obtusely rectangular above 
and below ; umbonal slope angulated. 2.— California. 
! A Rupicola, Lam. 10, and A. Longirostris, Lam. 4, are Corbule. 
