1849.] 155 



Melania 7iebidosa. Elongate conoidal ; volutions 6 or 7, with revolving raised 

 lines ; whorls of the spire carinated below the middle, above which they are lon- 

 gitudinally ribbed, and have 2 or 3 revolving granulated lines ; granules com- 

 pressed ; aperture widely elliptical ; colour ochraceous, with brownish-black 

 stains. 



Inhabits Savannah River. 



Melajiia percarinata. Elongate conoidal ; volutions of the spire with a cari- 

 nated line below the middle, and a revolving granulated line above ; body whorl 

 with a granulated revolving line near the suture, and 3 carinated lines, the superior 

 one largest, the lower one fine ; colour dark olive brown. 



Inhabits Savannah River. 



Melania symmetriea,. Subulate ; whorls 9, slightly convex, with longitudinal 

 slightly curved, narrow ribs, interrupted near the suture by a revolving granu- 

 lated line; ribs on the body whorl not extending as far as the middle; margin of 

 labrum profoundly rounded; colour ochraceous and black. 



Inhabits Savannah River. 



Near the apex, two or three volutions have a fine granulated carinated line. 



The folloviing neio and interesti7ig Shells are from, the coasts of Loiuer California 

 and Peru, and were 'presented to the Academy by Dr. Thomas B. Wilson. 



SOLECARDIA, Con. 



Shell bivalve, equivalve ; hinge with 2 diverging cardinal teeth, and a linear 

 oblique cartilage pit between; cardinal plate profoundly grooved on each side of 

 the teeth; muscular impressions 2, small, rounded, remote from the margins, 

 particularly from the base ; pallial impression entire. 



S. ehurnea. Oblong oval, equilateral, ventricose, thin ; extremities nearly 

 equally rounded; basal margin arched; valves white, shining, minutely sha- 

 greened, towards the base minutely rugose, with fine impressed radiating lines; 

 concentric lines towards the base finely waved, indenting the margin. 1 2-10: 

 8-10. 



In this singular bivalve the pallial impression shows no junction with the 

 adductor impressions, but joins the extremities of the cardinal plate. The mus- 

 cular impressions are as distinct on the exterior as on the interior. 



Petricola. 

 P. sinuosa. Subtriangular ; inflated anteriorly; profoundly sinuous pos- 

 teriorly ; ribs radiating, prominent, acute, except towards the anterior margin, 

 where they are replaced by closely-arranged lines ; basal margin profoundly 

 sinuous ; within brown, cavity of umbo white ; cardinal teeth prominent, 2 in 

 one valve, and one broad one in the other. 8-10 : 6-10. 



Family Anatenidce. 



Cyathodonta, Cc7i. 



An inequivalved bivalve ; hinge with a broad, not very projecting, cartilage 

 fosset, which is carinated near the margin ; muscular impressions rounded, indis- 

 tinct ; pallial impression with a large rounded sinus. 



