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. Candidus.* Renieri. — Ch. f. 43.^ — S. Strigilatus 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 strise ; ventraledge straightish, 

 sub-incurved in the middle : an oblique and an erect tooth in each 

 valve (in one valve the former rudimentary) : nymphse distinct, a. . \^. 

 — WIediterranean, cfc. 



S. SoLiDUS. 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 posteiior 

 straight and sub-bifid, the other oblique : inside white. If . . 2^. 

 — Peru. 



S. Inflexus. Wood. G. C. t. 32./. 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. Orbiculatus. Gray in TV. S. f. 4. — Psammobia 0. 

 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 nymphse 

 internally distinct. U . . -^-. — S. America 1 



S. Costatus. Say. Jour. A. N. S. Phil. 2. p. 315. — S. 

 Sayii. Grif. Cuv. Mol. t. 31. — Solecurtus C. Say. Amer. 

 Cone. t. 18. — Conrad. Ayn. C. t. 24./. 2. Elongated elliptical, 

 very compressed, smooth, anterior side thrice as long r Vposterior ; 

 very thin, rounded at each end, under a yeUowish 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 rib spreading and 

 becoming obsolete towards the ventral edge. 1 J. — New Jersey. 



S. Medius. Sow. in Beechey Zool. t. 43. /. 2. — Mach^ra 

 NiTiDA. Gould Mas. p. 33. f. 25,6. Oblong, Ugamental 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. 2^. — N. America. 



S. Maximus. Wood G.C.3\.f. 3.--W. t. 3./. 16.— S. Gigas, 



