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Bulletin 33 



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REMARKS ON VIRGINIA EOCENE FOSSILS 

 By Kathertne Van Winkle 



The following notes and descriptions are based on material 

 collected by members of the first cruise of the Ianthina in Vir- 

 ginian waters in 1897. Most material, then new, has been sub- 

 sequently described by members of the Maryland Geological Sur- 

 vey ; and interesting geographic data on the Virginian beds have 

 been published by members of the Survey of that State. How- 

 ever, these few additional notes seem worthy of publication. 



Genus LEDA Schumacher 



Leda coelatella, n. sp. PI. 1 Figs. 4, 5 



Specific characterization . — Size and general form as indicated 

 by the figures and explanations ; rather thick ; of the ccelata 

 stock, but differing from the Claiborne form by its smaller size, 

 less inflation medially, less relative contraction posteriorly and 

 especially by its more primitive surface marking — great diagonal 

 rugae of nearly equal strength across the whole valve with only 

 a down-dipping in the young stage as they approach the umbonal 

 ridge, whereas in cas/ata these rugae are strong only on the sector 

 just posterior to the middle; in advance of the same such mark- 

 ings become fainter, swing upward across the channel from beak 

 to anterio-basal margin and finally resume their former direction 

 till they reach the margin of the shell ; lunule, escutcheon and 1 

 post- umbonal markings very similar to those of ccelata, though 

 the radial ribs are more generally and coarsely granulate, thus 

 recalling coelatoides. 



Types and specimens figured. — Paleontological Museum, Cor- 

 nell Univ. 



Horizon. — Probably lower St. Maurice Eocene. 

 Locality. — New Castle, Va. Collected by 1st Ianthina Ex- 

 pedition, '97. 



