TRIBE SOLENID. 11 
the margin: anterior side quadruple the length of the posterior, 
and rounded at the extremity: gape very large. 3!,.. 11.—Isle of 
Plata. 
G. Brevis. Sow. Z. P. 1834. Abbreviated-ovate, thin, pel- 
lucid, striated : anterior side seven times as long as the posterior. 
z+. 4.— Gallapagos. 
G. Hyauina. Sow. Z. P. 1834. Oval, whitish, hyaline, 
smoothish, with the back longitudinally striated : posterior side 
short ; gape equal to $dsof the length of the shell. ®;3!.—Lord 
Hood's Island. 
G. Rucorosa. Sow, Z. P. 1834. Oblong, whitish, striated, 
rugulose ; the posterior wrinkles near the gaping margin, crowded 
and acute ; gape extremely long. %;4.— Gallapagos. 

TRIBE SOLENIDZ. 
Shell transversely elongated, destitute of accessary pieces, and 
gaping at the lateral extremities only ; ligament external. 
SOLEN. 
Equivalve, transversely elongated, gaping at both extremities ; 
beaks very small, prominent ; primary teeth small, varying in 
number, sometimes none, seldom inserted in a cardinal pit ; liga- 
ment external, 
* Hinge terminal. 
S. Vacrna.* Lin. 1113 —D. p. 57.—Lam. 1.—Don. t. 110. 
— Mont. p. 48.—Turt. B. p.79.—W. t.3.f.3. Sub-cylindrical, 
becoming more compressed towards the truncated anterior extremity, 
orange-yellow sometimes stained with brown : a stricture across the 
posterior extremity which is slightly oblique : a single tooth in each 
valve, the opposite sides strengthened by arib. 1..5.— Europe. 
S.Corneus. Lam. 2.—Del.t. 2. f. 2. Small, linear, straight, 
margins nearly parallel, uniform horn-ccloured, epidermis very 
thin : hinge with a single tooth in each valve. 2.—Java. 
S. Vacinorpes. Lam. 3.—Del. t. 2. f. 3. 8. Corneus, 
W.S.t.1.f. 2. Linear, slightly curved, reddish ; ‘hinge with 
one tooth in each valve. 32.—Isles of New Holland. 
S. Srrreua.* Lin. 1113.—D. p. 58.—Lam.4.—Ch, f. 29.— 
Don. t, 46.—Mont. p. 46.—Turt. B. p. 80.—W. t. 3. f. 1. 
Straight, with an olive brown cuticle, which is darkest at the 
posterior extremity: a single tooth and a remote lateral lamina in 
one valve, in the other, two besides a lateral inclined tooth, corres- 
ponding with the opposite lamina. 1..7.—Hurope. 
S. Ensis.* Lan. 1114.—D. p. 59.—Lam. 5.—Ch.f. 29, 30.— 
