MAETLAND GEOLOGICAL SURVEY 357 



Occurrence. — St. Mary's Formation. St. Mary's Eiver. 

 Collections. — Maryland Geological Survey, Johns Hopkins University, 

 U. S. National Museum. 



AsTARTE PARMA Dalll 

 Plate XCIV, Fig. 15. 



Astarie (Axhtarotha) parma Dall, 1903, Trans. Wagner Free Inst. Sci., vol. iii, pt. vi, 

 p. 1493, pi. Ivii, flg. 23. 



Description. — " Shell very flatly compressed, inequilateral, rostrate, the 

 beaks at the anterior third low, acutely pointed, slightly recurved ; lunule 

 narrow, deeper than wide; escutcheon, narrow, deep, as long as the 

 posterior slope, which is almost straight; sculpture of the beaks with 

 about five small, fine ribs, close together, followed by three or four very 

 distant, much wider ripples, obsolete towards the ends and ventral 

 margin, with a few irregularly spaced linear concentric sulci beyond; 

 posterior dorsal profile slightly arcuate, basal margin slightly emargi- 

 nate behind; anterior end rounded, posterior end pointed; inner ventral 

 margins crenate; hinge-plate broad and flat with two long, narrow 

 cardinals in each valve. Height, 25.0, length, 38.5, diameter, 7.0 mm. 



"This curious form differs from per plana by its more compressed, flatter, 

 and more acutely pointed valves, and by its umbonal sculpture." Dall 

 1903. 



Occurrence. — Calvert Formation. Skipton, Plum Point. 



Collection. — U. S. National Museum. 



Order ANOM ALODESMACEA. 



Superfamily ANATINACEA. 

 Family PANDOR1D7E. 



Genus PANDORA Hwass. 

 Subgenus CLIDIOPHORA Caipenler. 



Pandora (Clidiophora) ceassidens Conrad. 

 Plate XCV, Figs. 1, 2. 



Pandora crassidens Conrad, 1838, Fossils of the Medial Tertiary, p. 3, pi. i, flg. 2. 

 Pandora crassidens Conrad, 1803, Proc. Acad. Nat. Sci. Phila., vol. xiv, p. 572. 

 Pandora crassidens Meek, 1864, Miocene Cbeck List, Smith. Misc. Coll. (183), p. 12. 



