64 Bui^LETlN 31 64 



Leda magnopsis, n. sp., PL 24. Fig. 8. 



In a coquina-like rock labelled "Rock Swamp" a few miles 

 south-east of Springfield, S. C, is found a fragmentar}" Leda 

 which we took at first to be Lea's L. luagjia. But instead of 

 having a smooth radial band extending down the post-umbonal 

 slope as in magna and in lisboncnsis, the concentric liration swings 

 over this area but little diminished in strength. Just behind, 

 there is a deep radial furrow, but the concentric or diagonal lin- 

 ing is not to be seen between this furrow and the margin of the 

 shell as in lisbonensis or Lea's species. 



Type. — Paleont. Lab. Cornell Univ. 



Leda bastropensis, PI. 24. Figs. 9, 10. 



Leda bastropensis Harris, Proc. Phila. Acad. Nat. vSci. 1895, p. 46, pi. i, 



fig. 3- 

 Leda bastropensis Ball, Trans. Wag. &c., '95, p. 578. 



//arris's original description. — General form as figured ; medial por- 

 tions of the valves vi^ith regular, strong, concentric striae ; striae obsolete on 

 the anterior end and on the post-umbonal slope, the latter with a shallow 

 furrow extending from the umbo to near the extremity of the valve ; within 

 the valve a raised line or ridge, emanating from the umbonal region and ex- 

 tending along beneath the hinge finally terminates in the middle of the pos- 

 terior end and is there slightly enlarged. 



This species differs from L . plicata Lea in its lack of striation over 

 portions of the exterior, and the more central positions of the umbones. 

 From L. viater Mr., bastropensis is distinguished by its want of anterior rad- 

 iating sulci, its lack of post-umbonal striation and b}- its form. This is 

 readily distinguished from L. albiriipina Har., since it lacks the smooth, 

 Yoldia-like aspect about the umbones so characteristic of that species. 



Type and specimen figured . — Univ. Tex. Coll. 



Localities and horizon. — St. Maurice stage at Starr-Zapata 

 Co. line on the Rio Grande ; and i mile below Milam-Burleson 

 Co. line, Brazos River, Tex. ; Ft. Gaines, Ga. ? 



Leda bella Conrad, PI. 24. Figs. 11-16. 



Nucula bella Con., A. J. S., 183.5, vol. 33, p. 343. 



Nucula plicata Lea, Cont. to GeoL, 1833, p. 85, pi. 3, fig. 64. 



Leda bella Con., Proc. Phila., Acad. ,1854, p. 29. 



Nuculana plicata Con., Am. Jr. Conch., vol. i, 1865, p. 13. 



Leda plicata de Greg., Faun. Ala., '90, p. 189, pi. 23, figs. 6-10. 



Nuculafia plicata Cossm., Notes Compl. '93, p. 15. 



