28 



60 



purpuratus Conrad, Amer. Marine Conch., p. 10, pi. 2, f. 



I, 1 83 1. Not of Lamarck. 



dislocatus Holmes, Post-Plio. Fos. S. C, p. 12, pi. 2, f. 12, 

 1858 ; Hilgard, House of Rep., Ex. Doc. 1, pt. 2, p. 888, 

 1878. 



irradians var. dislocatus Dall, Bull. 37, U. S. Nat. Mus., p. 

 34, 1889 ; Singley, Fourth Ann. Rept. Texas Geol. Surv., 

 324, 1892. 



gibbus var. dislocatus Dall, Trans. Wagner Inst. Sci., 3, pt. 

 4, p. 746, 1898 ; Idem, pt. 6, p. 1615, 1903. 

 Remarks : Linnaeus' description of 0. gibba was based on the 

 drawing of a Jamaican Pecten by Browne (Civil and Nat. 

 Hist. Jamaica, p. 41, pi. 40, fig. 10, 1756J. According to 

 Dr. Dall, this is identical with dislocatus Say. 

 Distribution. — Hatteras to Brazil and west coast of Africa. 

 Miocene to Recent. Gulf coast. — Recent : Cedar Keys, 

 Fla ; Matagorda, Corpus Christi, Texas. Pleistocene : 

 Orient and North Creek, Fla. ; New Orleans well of 1856 

 at 235, 480, 546 feet ; Lake Borgne borings (?); Knapp's 

 wells, Terrebonne Parish No. 1 at 2000-2150, 2250-2450, 

 No. 3 at 570-700, 1150-1200, 1200-1300, 1330-1375, 1400-1440, 

 1443-1470, 1500-1525 feet. 



(Plagioctenium) gibbus irradians Lamarck 



Pecten irradians Lamarck, An. s. Vert., 6, p. 173, 1819. 

 concentricus Say, Jour. Acad. Nat. Sci. Phila., p. 259, 1822. 

 irradians Gould, Binney'sEd. Invert. Mass., p. 199, fig. 496, 

 1870 ; Dall, Bull. 37, U. S. Nat. Mus., p. 34, pi. 53, fig. 



II, 1889; Singley, Fourth Ann. Rept., Geol. Surv. Texas, 

 p. 324, 1892. 



gibbus var. irradians Dall, Trans. Wagner Inst. Sci., vol. 3, 

 pt. 4, p. 748, 1898 ; Vanatta, Proc. Acad. Nat. Sci. Phila., 

 vol. 55) P- 756, 1903. 

 Distribution. — New Jersey to Texas. Pleistocene to Recent. 

 Gulf coast. — Recent : Tampa, Florida ; Horn Island 

 Miss. ; Chandeleurs, La. ; Corpus Christi, Galveston ? 

 Texas. Pleistocene: North Creek, Manatee Co., Fla.; 



