326 SYSTEMATIC PALEONTOLOGY 



Sportella recess a n. sp. 

 Plate LXXXVII, Figs. 8, 9, 10. 



Description. — Shell blunted-ovate, not greatly inflated; inequilateral, 

 anterior part the longer; beak slightly projecting; anterior dorsal margin 

 nearly straight, posterior one curved; posterior end more blunted than 

 anterior one; basal margin gently curved; pallial line faint; adductor 

 scars very faint, anterior one elongated, posterior one more rounded; 

 external surface with fine, irregular, concentric, incremental lines. 



Length, 4.6 mm.; height, 3.7 mm.; diameter, LI mm. 



Occurrence. — St. Mary's Formation. Cove Point. Calvert For- 

 mation. Eeed's. 



Collection. — Maryland Geological Survey. 



Sportella patuxentia n. sp. 

 Plate LXXXVII, Fig. 11. 



Description. — Shell triangular, depressed, thick, inequilateral; an- 

 terior side the longer; anterior side declining, slightly curved; anterior 

 end acutely rounded; posterior side very short; posterior end bluntly 

 rounded; teeth strong; muscle impressions distinct; anterior one elon- 

 gated and narrow, posterior one rounded; pallial line distinct, ragged, 

 somewhat irregular; exterior surface with irregular concentric lines or 

 grooves. 



Length, 8 mm.; height, 6 mm.; diameter, 1.75 mm. 



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



Collection. — Maryland Geological Survey. 



Genus HINDSIELLA Stoliczka. 



Hindsiella acuta Ball. 



Plate LXXXVII, Figs. 12a, 12b, 13. 



Hindsiella acuta Dall, 1900, Trans. Wagner Free Inst. Sci., vol. iii, pt. v, p. 1138, 

 pi. xlv, fig. 9. 



Description. — " Shell small, cuneate, inflated, subequilateral, the 

 posterior side broader and rounded, the anterior narrower, more pointed 

 and decurved; anterior dorsal margin declining, posterior arcuate; 



