M0I.I.USCA OF THE GuivF OF MEXICO 33 



Distribution. — Antilles to Rio la Plata. Gulf coast. — Cedar 

 Keys, Fla. Chipolan Miocene (?) 



Genus 1V3YT!LUS Linnseus 



Gonradianus d'Orbign}^ Prodr. Pal., 3, p. 127, 1852 ; Dall, Tr- 

 Wagner Inst. 3, pt. 4, p. 787, '98. 



mcrassatus Conrad, Am. Jour. Sci., 41, p. 347, 1841 ; Fos- 

 Medial Tert., p. 74, pi. 42, fig. 4, '45 ; Tuomej^ and 

 Holmes, Pleoic. Fos. S. C, p. 32, pi. 14, figs, i, 2, 1857 : 

 Harris, Bull. Amer. Pal. i, No. 3, p. 87, '95. Not incras- 

 sata Deshayes, 1830. 



Mytiloconcha incrassata Conrad, Proc. Acad. Nat. Sci. Phila., 

 for 1862, p. 291. 

 Distribution. — Miocene of New Jersey, Maryland, the Caro- 

 linas, and the Galveston artesian well, Texas, at 2384-2871 

 feet (Harris). 

 exustus Linn., Syst. Nat. ed. X, p. 705, 1758 , Dall, Bull. 37, 

 U. S. Nat. Mus., p. 38, '89 ; Singley, Fourth Ann. Rept. 

 Texas Geol. Surv., p. 325, '92 ; Vanatta, Proc. Acad. 

 Nat. Sci. Phila., vol. 55, p. 756, '03 ; Mitchell, List Texas 

 Shells. 



didejis L/inn. , Syst., Nat., ed. XII, p. 1157, 1767. 



domingensis Lamarck, An. s. Vert., 6, p. 121, 181 9 ; d'Orbig- 

 ny, Moll. Cuba, 2, p. 328, 1845. 

 Distribution. — Charleston to Bahia, Brazil. Pliocene to Re- 

 cent. Gulf coast. — Crooked Isl., Calhoun Co., Fla. ; Cor- 

 pus Christi and Lavaca Bays, Tex. Pliocene: Caloosa- 

 hatchie and Shell Creek, Fla. 

 hamatus Say, Jour. Acad. Nat. Sci. Phila., 2, p. 265, 1822 ; Bin- 

 ney's reprint of Say, pp. 91, 204, pi. 50 ; Dall, Bull. 37, 

 U. S. N. M., p. 38, '89; Singley, Fourth Ann. Rept. 

 Geol. Surv. Texas, p. 325, '92 ; Dall, Trans. Wag. Inst. 

 Sci., vol. 3, pt. 4, p. 789, '98 ; Clark, Pleistocene of Mary- 

 land, Md. Geol. Surv., p. 203, pi. 60, figs. 5, 6, 1906. 



striatus Barnes, Am. Jour. Sci., 6. p. 364, 1823 ; Say, Am. 

 Conch, 5, pi. 50, 1832. 



