MARYLAXD GEOLOGICAL SURVEY 323 



Subgenus L/tVICARDlUM Swainson. 



CiAKDiUM (L^vicardium) mortoni Conrad. 

 Plate LXXXVI, Figs. 7a, 7b. 



Cardium Mortoni Conrad, 1831, Jour. Acad. Nat. Sci. Phila., voL vi, 1st ser., p. 259, 



pi. X, figs. 5, fi, 7. 

 Oardium Mortoni Gould, 1841, Invert. Mass., p. 91. 

 Liocardium Mortoni Stimpson, 1860, Check List E. Coast Shells, p. 2. 

 Lcevicardium Mortoni Perkins, 1869, Proc. Bost. Soc. Nat. Hist., vol. xiii, p. 150. 

 Liocardium Mortoni Dall, 1889, Bull, xxxvii, U. S. Nat. Mus., p. 54, pi. Iviii, fig. 8. 

 Cardium {Lcevicardium) Mortoiri Dall, 1900, Trans. Wagner Free Inst. Sci., vol. iii, 



pt. V, p. 1111. 



Description. — " Shell subovate, oblique, slightly ventricose, thin, desti- 

 tute of ribs or radiating striae ; white, covered with a pale brown epidermis 

 darker towards the base and wrinkled at the ends; within striated, and 

 of a yellow colour; margin entire or obsoletely serrated, whitish, with 

 generally an oblong black or dark purple spot on the posterior side. 



" This shell has not the polish nor distinctly serrated margin of C. ser- 

 ratum to which it is nearly allied ; the striffi are occasionally obsolete or 

 only slightly serrate ; the margins towards the anterior end, and the 

 young shells are marked with angular fulvous spots, similar to the young 

 of C. Icevigatum and several other shells.'' Conrad, 1831. 



Occurrence. — Choptank Formation. Jones Wharf {fide Dall). 



Collection. — U. S. N"ational Museum, 



Superfamily LEPTONACEA. 

 Family GALEOMMATID/E. 



Genus SOLECARDIA Conrad. 

 Subgenus SPANIORINUS Dall, 



SoLECARDiA (Spaniorinus) cossmanni Dall. 

 Plate LXXXVII, Figs, 1, la, 2, 3, 1, 



Solecardia (Spaniorinus) Cossmanni Dall, 1900, Trans. Wagner Free Inst. Sci., vol. 

 iii, pt. V, p. 1125, pi. xlv, figs. 27, 27a. 



Description. — '' Shell thin, nearly equilateral, rounded at both ends, 

 the posterior end blunter, shorter, and higher than the anterior; surface 

 with rather irregular obvious incremental lines, smoother near the 



