OF CONCHOLOQY. 105 



Locality. — Patuxent Eiver, Virginia. 



Observations. — Having two entire specimens, large and small, 

 which perfectly agree in their characters, I consider this a 

 very distinct species, allied to M. suhmortoni, D'Orbigny. 



Var. ^.— SHghtly produced and subcuneiform posteriorly. 

 CHAMID.E. 



ARCINELLA. 



Arcinella coenuta, Conrad. 



Description. — Orbicular-cordate ; radiating ribs very spinous ; 

 spines very thick, tubular ; interstices deep, rugoso-punctate ; 

 lunale broadly cordate ; buccal side granulated, 



Ghama arcinella, Tuomey and Holmes (not Lamarck). Plio- 

 cene Fossils of South Carolina, p. 22, pi. vii.; fig. 4, 5, 6. 



Observations. — This species differs from the recent one in 

 being larger, much thicker, and more especially in having 

 fewer spines, which are much thicker than in the recent 

 species, and not in two series of thick and thin spines, which 

 characterize the latter, 



TELLINID.^, 

 Cyprimeeia Peeuviana, Conrad. — PI. 9, fig. 1. 



Description. — Subtriangular, inequilateral, lentiform, pos- 

 terior extremity opposite the end of the cardinal line ; ventral 

 margin rounded. 



Locality.— KvciOion^Q,, Peru. Dr. Kuschenberger. 



Observations. — Mr. Darwin refers to a few fossils, an Ammo- 

 nite, Baculite, ko,., at Conception, which he inclines to believe 

 belong to an Older Tertiary formation. I have no doubt of 

 their Cretaceous origin, and the present genus is an additional 

 proof of the presence of Cretaceous strata in Peru. 



ANOMIIDiE. 



DIPLOSCHIZA, Conrad. 



D. cretacea, Conrad.— pi. 9, figs. 2, 3. 

 American Journ. of Conch., vol. i., p. 77. 



TERBBEATULID^. 

 Terebeatulina filosa. Con.— pi. 9, figs. 4, 5. 



American Journ. of Conch., vol. i., p. 77, 



Observations. — This species is more nearly of the outline of 

 T. gracilis of Europe than of T. Gaudalupse, Roemer, a species 

 of Texas. The latter has a more tapering and prominent 

 umbo and a shorter hinge line, and the smaller valve much 

 more convex. 



