52 Bulletin 9 244 



For Aldrich's original description, op. cit.' 



Without the type specimen before us we are very much in- 

 clined to regard this as the young of fig. 13, pi. 8. 



Localities. — Alabama : Choctaw Corner. 



Type. — Aldrich's colledlion. 



Leda protexta. PI. 8, fig. 13. 



Syn. Nuculana protexta Con., Amer. Jour. Conch., voL i, 1865, p. 147, 

 pi. II, fig. 6. 

 Leda protexta Heilp., Proc. Acad. Nat. Sci. Phila., iSSo, p. 365. 

 Leda protexta Aid., Bull, i, Geol. Surv. Ala., pp. 50, 53, 57, 1886. 



Cojtrad's original description. — "Elongated, slightly ventri- 

 cose, with closelj' arranged, minute thread-like concentric lines, 

 distindl and rugose on the anterior submargin, which is flattened, 

 or broadly and slightl)' furrowed. Upper margin oblique, medi- 

 ally rectilinear, reflexed at the end ; posterior extremity above 

 the middle and on a line with the anterior end ; posterior ventral 

 margin obliquely truncated. 



'"Locality. — Alabama. Dr. Showalter. " 



This species shows considerable variation in outline and surface 

 ornamentation. Older Lignitic specimens, from Gregg's landing 

 show finer striae and less sharply defined post-umbonal slope. 



We are well aware that Gnbb gave the name protexta to a 

 species {L. protexta Gabb, Jour. Acad. Nat. Sci., Phila., vol. iv, 

 i860, p. 303) five years before Conrad named this form. Since 

 Mr. Stanton, our best authority on invertebrate Cretaceous pal- 

 eontology, writes that Gabb's species just referred to is a true 

 Leda, it follows as a matter of course that the same specific name 

 cannot be permanently retained for the Lignitic form under dis- 

 cussion. 



The indications are however, that when all the Eocene stages 

 have been carefully gone over, this L. protexta Con. will prove 

 but an ancestral form of a species named by Conrad himself sev- 

 eral years before 1865. Hence, feeling that the name protexta is 

 doing less harm in Tertiary literature than a new and perhaps 

 unnecessary name might do, the latter is avoided for the present. 



Localities. — Alabama : Woods Bluff ; four miles above Hamil- 

 ton Bluff, Alabama River ; Ozark ; Gregg's Land- 

 ing. Georgia : Ft. Gaines. 

 Type. — Acad. Nat. Sci., Phila.; improperly labelled by Heil- 

 prin "Claiborne, Ala." 



