TRIBE SOLENID&. 15 
elevated sub-direct internal cross-bar extending from the hinge but 
half way to the margin. 1..2.—Red Sea.—Epidermis very thin. 
S. Canpipus.*  Renieri.—Ch. f. 43.—S8. Srriemarus of 
British authors. Elongated oblong, breadth twice and a half the 
length, ends rounded; uniform white, marked with coarse ridges of 
growth, and anteriorly with curved radiating strigils: beaks sub- 
central, anterior slope with divaricating striez; ventraledge straightish, 
sub-incurved in the middle : an oblique and an erect tooth in each 
valve (in one valve the former rudimentary): nymphee distinct. +..13. 
— Mediterranean, §c. 
S. Souipus. Gray. Spic. Z. t. 3. f. 12. Solid ovate, narrower 
anteriorly, rounded at both ends, dull white, convex, with obsolete 
concentric wrinkles : umbones convex, sub-posterior, dorsal edge 
sinuated : two short and elevated teeth in each valve, the posterior 
straight and sub-bifid, the other oblique: inside white. 1}.. 23. 
—Peru. 
S. Inrtexus. Wood. G. C.t. 32. f.1, 2.—D. p. 62.—W. t. 
3.f.18. Elongated-oblong, greenish white under an orange-brown 
epidermis, posteriorly broader, anteriorly more than twice as long as 
posteriorly, ventral margin inflected, nearly smooth: inside white, 
two teeth in one valve and one in the other, besides a prominent 
convex radiating rib. 1..3. 
S. Orsicutatus. Grayin W. 8S. f. 4.—Psammosia O. 
Desh. Mag. de Z. 1839. Mol. t.7. Rounded-ovate, narrower, 
nearly smooth, polished, much shorter and obliquely rounded 
posteriorly, not at all angulated, under an uniform yellowish-olive 
cuticle white; hinge with an acute and semicircular tooth in one 
valve, an acute and a sub-laminar tooth in the other; the nymphe 
internally distinct. 14..3.—S. America ? 
S. Costatus. Say. Jour. A. N. S. Phil. 2. p. 315.—S. 
Sayti. Grif. Cuv. Mol. t. 31.—Sotecurtus C. Say. Amer. 
Cone. t. 18.—Conrad. Am. C. t. 24. f. 2. Elongated elliptical, 
very compressed, smooth, anterior side thrice as long as posterior ; 
very thin, rounded at each end, under a yellowish olive cuticle pale 
violet red, with not more than three whitish rays : teeth two (some- 
times obsolete) in each valve, the posterior one upright, the other 
bent forwards: an internal direct longitudinal mb spreading and 
becoming obsolete towards the ventral edge. 15.—Nem Jersey. 
S. Mepius. Sow. in Beechey Zool. t. 43. f. 2.—Macuamra 
Nitrpa. Gould Mas. p. 33. f. 25,6. Oblong, ligamental edge 
elongated and straightish, ventral slightly curved, posteriorly 
rounded and very short, anteriorly sub-attenuated and obtuse, smooth 
white or livid under a greenish or brownish yellow shining cuticle : 
inside white, with a posterior cross-bar: three teeth in one valve, 
two in the other. 24.—N. America. 
S. Maximus. Wood G. C.31. f. 3.—W. t. 3. f. 16.—S. Gieas, 
