22 Bulletin 34 54 



subovata Say 



PecUinculus sjibovatus Ssiy , Jour. Acad. Nat. Sci., Phila. , ist 

 Ser., vol. 4, p. 140, pi. 10, fig. 4, 1824; Conrad, Fos. 

 Shells Tert. Formations, p. 17, pi. 2, fig. 3, 1832. 

 subovata Dall, Trans. Wagner Inst, Sci., vol. 3, pt. 4, ]). 

 611, 1898; Aldrich, Manuscript. 



Remarks. — This species includes the varieties htomeyi and 

 plagia Dall. 



Distribution. — Vicksburgian Oligocene of Martin, Fla.; Mio- 

 cene of Virginia, Maryland, and Florida. Bascom No. i 

 well, Mobile, 1550- 1556 feet, Oak Grove horizon ; No. 2 

 at 1 241, 1600 and 1800 feet. 



Genus ATRINA Gray 

 rigida Dillwyn 



Pin7ia rigida Dill., Cat. p. 327, 1817 ; Reeve, Conch. Icon., 

 Pi7ina, pi. 5, fig. 7, 1858. 



seminuda Lam., An. s. Vert., vol. 6, p. 131, 1819. (Not 

 Reeve); Holmes, Post-Plio. Fos. S. C, p. 14, pi. 3, fig. 2, 

 i860 ; Singley, Fourth Ann. Rept. Texas Geol. Surv. , p. 

 324, 1892. 



muricata, Hilgard, House of Rep. Ex. Doc. i, pt. 2, p. 888, 

 1878; Dall, Bull. U. S. Nat. Mus. No. 37, p. 36, 1889; 

 Singley, loc. cit., p. 324, 1892 ; and of many American 

 authors but not of Linnaeus nor of Reeve. 



rigida Dall, Trans. Wagner Inst., vol. 3, pt. 4, p. 663, 

 1898 ; Vanatta, Proc. Acad. Nat. Sci., vol. 55, p. 756, 

 1903. 

 Distribution. — Hatteras to Central America. Pleistocene to 



. Recent. Gulf Coast.— Recent : Cedar Keys, St. Joseph's 

 Bay (Calhoun Co.), Fla. ; Chandeleur Islands, La. ; Gal- 

 veston, Corpus Christi, Matagorda Bay, Mustang and 

 Padre Islands, Texas. Pleistocene : Lake Borgne borings 

 (Hilgard); New Orleans pumping station No. 7. 



serrata Sowerby 



Pinna serrata Sowerby, Tank. Cat. App., p, 5, 1825 ; Reeve^ 

 Conch. Icon., Pinna, 34, fig. 65, 1859. 



