194 PROCEEDINGS OF 



PECTEN.— (Lorn.) 



Pecten Hmnphreysii, pi. 2, fig. 2. Suborbicular, inferior valve convex ; superior 

 flat, and with about seven remote, narrow, convex ribs, and concentrically wrinkled ; 

 towards the apex is a concave depression ; ears equal, sides direct and straiglit ; infe- 

 rior valve with the ribs wide, approximate, plano-convex and longitudinally striated ; 

 one of the ears emara;inate at base. 



Localities : Near Fairhaven, Anne Arundel county, Md. Mr. Wilkinson's farm, 

 in Calvert county. I am indebted to Dr. Humphreys, of Annapolis, for the loan of 

 the specimen figured, that which I found at Fairhaven being too imperfect for the 

 purpose. I gladly attach the name of this gentleman to the species, in considera- 

 tion of his love of and proficiency in scientific pursuits. 



Of two specimens in the collection of the college at Annapolis, the largest mea- 

 sures three inches from beak to base. 



BISTOTJEA.— {Say.) 



Dispotaa constricta, pi. 1, fig. 2.— Shell irregular, elevated ; laterally compressed, 

 marked with simple lines of growth ; apex prominent, with one or two minute vo- 

 lutions ; diaphragm very profound. 



Locality : Captain Ilance's Landing, Calvert Cliffs, Maryland. 



SCALARIA.— (Lam.) 



Scalaria expansa, pi. 2, fig. 3 — Shell acutely ovate, moderately thick, with nu- 

 merous robust recurved ribs, twelve in number, counting from the summit of the 

 aperture to the reflected lip, inclusive ; wliirls profoundly ventricose at the sides, 

 somewhat flattened above ; four or five in number. 



Locality : St. Mary's river, Maryland. 



Two specimens of this fine Scalaria were obtained by Mr. Markoe, and none 

 other is known to have been discovered. 



BUCCINUM.— (Lo/n.) 



Buccinum integrum, pi. 2, fig. 5.— Shell short, subfusiform or elliptical ; smooth ; 

 destitute of ribs or striae; spiro conical, the volutions convex; aperture elliptical, 

 about half the length of tlie shell ; columella thick ; labium reflected. 



Localities : St. Mary's river and Calvert Cliffs, near the mouth of Patuxcnt 

 river. 



SCUTELLA.— (Lam.) 



Scutella Aberti. — Discoidal, orbicular, very much depressed, but swelling to- 

 wards the middle, and depressed at the apex ; diameter five and a half inches. 



Locality : Patuxent river, St. Mary's county, Maryland. 



This large Scutella is very abundant; but those I have, at present, are too imper- 

 fect for minute description. A figure of it will bo published when specimens in 

 better condition shall bo obtained. It is dedicated to my scientific friend Colonel 

 J. J. Abert, of Washington, whose name it gives mo great pleasure thus to con- 

 nect with the tertiary rocks of Maryland. 



