262 TESTACEOUS MOLLUSCA. 
A. Tarentina.* Lam- 6.—Phil. p. 76.—. vol. 2. p. 99.— 
E. t. 177. f. 8.—Ch. f. 725.—Mytitus Hirunpo. Poli. 2 t. 
32 f. 17 to 21.—do. var. E. D. p. 321.—A. Acutzata. Risso. 
Thin, yellowish grey, usually rayed with brown, generally worn 
smooth, but armed when perfect with numerous very narrow long 
depressed scales: valves nearly equal in size but not always in 
convexity: ear prominent, sublanceolate : body narrow, very ob- 
liquely projecting ; tail rather long, the sinus always more or less 
profound and obtuse.—3. Mediterranean, &c. 
A. Artantica. Lam. 8.—E. 2. p. 101.—Myrtitus Hirunpo. 
Var. A & B. D. p. 321.—W. t. 12. f. 42.—Gualt. t. 94. B. 
—Ch. f. 722,3.—dAdan Sen. t. 15. f. 6. Brown, with the wing 
broad, rounded, and scarcely oblique: valves unequal in size : tail 
elongated ; body rounded, small, not very oblique. 2}.—Atlantic 
Ocean. 
A. Sauamunosa. Lam. 9. Thin, fragile, yellowish or red, 
with a few obsolete cloudy markings, somewhat roughened by a 
few distant radiating rows of scales; wing broad and obliquely 
rounded, tail very short and ear shaped ; anterior sinus shallow.— 
Base. 13. Brasil. Tiger Bay ? 
A. Papitionacea. Lam. 10. Thin, pellucid, whitish, inter- 
ruptedly rayed with chesnut or purplish brown, tail almost obso- 
lete ; body moderately long, somewhat rounded; ear prominent.— 
Var. With the rays greenish, spotted with brown. 1 Australia. 
A. Cosrettata. Lam. 11. Thin, oblong-elliptic, oblique, 
brownish, fulvous, with minute tubercles so disposed as to-resem- 
ble ribs: hinge short; no tail: within but partly nacreous. Last 
Indies. 
A. PuysoiwEs. Lam. 12. Very thin, very fragile, ‘hyaline 
and subvesicular, veined with a few ferruginous lines ; the wing 
very oblique; tail very short if any. + New Holland on Sertularie. 
A. Virens. Lam. 13. Very small, thin, smooth, pellucid, 
greenish, margin somewhat rayed ; tail short and ear shaped. Va- 
riety.— Ch. 721. With the wing larger and rounder. 3 New 
Holland. 
A. Vespertitio. Desh. in Lam. vol. 7, p. 102. Brownish 
black, inequivalve, concentrically substriated, with the wing broad, 
round and scarcely oblique, tail elongated, narrow, fragile: hinge- 
margin narrow; nacre reddish ; with two small obtuse teeth and 
the rudiments of a posterior lateral one. The sinus for the byssus 
forms a right angle on the right valve.' 
' This description is not inapplicable to the Morio of Leach, 
of whose figure in the Zoological Miscellany, (2. ¢. 38. f. 2.) we have 
