200 SYSTEMATIC PALEONTOLOGY 



There occurs rather abundantly at Greensboro in association with this 

 species a small form ranging in length from 2.5 mm. to 3.5 mm. This 

 may represent C. lunata (Say), which has not hitherto been recognized 

 in the Miocene of this region. 



Length, 14 mm. ; diameter, 6 mm. 



Occurrence. — St. Mary's Formation. St. Mary's River, Cove Point, 

 Langley's Bluff. Choptank Formation. Jones Wharf, Governor Run 

 (lower bed), Greensboro. Calvert Formation. Plum Point, 3 miles 

 west of Centerville. 



Collections. — Maryland Geological Survey, Johns Hopkins University, 

 TJ. S. National Museum, Philadelphia Academy of Natural Sciences, 

 Cornell University. 



Columbella calvertensis n. sp. 

 Plate L, Fig. 8. 



Description. — Shell thick, elongate, eight- whorled ; spire elevated; 

 whorls slightly convex ; body whorl with about twenty-four narrow re- 

 volving grooves with flat interspaces about four times as wide ; whorls of 

 the spire with about six grooves ; lines of growth very faint ; mouth nar- 

 row ; labrum thick, with about fourteen coarse teeth ; canal short, slightly 

 curved. 



Length, 16 mm. ; diameter, 6.5 mm. 



Occurrence. — Calvert Formation. Plum Point. 



Collections. — U. S. National Museum, Maryland Geological Survey. 



Family MURICID/E. 



Genus MUREX Linne. 

 Subgenus PTERORHYTIS Conrad. 



MuREX (Pterorhytis) conradi Dall. 

 Plate L, Figs. 9a, 9b. 



Cerostoma umbrifer Tuomey and Holmes, 1856, Pleiocene Fossils of South Carolina, 



expl. pi. xxviii, fig. 14. (Not p. 141.) 

 Murex {Pterorhytis) Conradi Dall, 1890, Trans. Wagner Free Inst. Sci., vol. iii, pt. i, 



p. 143, pi. xii, fig. 11. 

 Ocenebra (.Pterorhytis) conradi Cossmanu, 1903, Essais de Paleoconch. Conip., vol. v, 



p. 43, fig. 3. 



