69 MOLlwUSCA OF THE GuLF OF MEXICO 37 



lignea Reeve, Conch. Icon., lo, Modiola, pi. lo, f. 71, '58; 



Ball, Bull. 37, U. S, N. M., p. 38, '89. 

 Modiolaria castanea Ball, Tr. W. I. S., 3, pt. 4, p. 266, '98. 

 Bistribution.— S. Carolina to St. Thomas. West Fla. (Ball). 



Genus CRENELLA Brown 

 divaricata d'Orbign}- 



Niiciilocardia divaricata A' Orh., in Be la Sagra, Hist. Pol. y 



Nat. Isla de Cuba, 2, p. 311, pi. 27, f. 56-59, 1847. 

 divaricata Gabb,' Trans. Am. Phil. Soc, 15, p. 252, '73 ; 

 Ball, Bull. 37, U. S. N. M., p. 40, '89 ; T. W. I. S., 3, 

 pt. 4, p. 803, '98 ; Maury, Bull. 29, Am. Pal., p. 194, pi. 

 26, f. 18, 1917. 

 decussata Ball, B. M. C. Z., 12, p. 235, '86. Not of Mon- 

 tagu. 

 Bistribution. — Hatteras to Barbados. West Florida. Mio- 

 cene to Recent. 



Genus LITHOPHAGA Bolten 



bisulcata d'Orbigny 



Lithodomus bisulcatus d'Orb., Hist. Pol. y Nat. Isla de 



Cuba, 2, p. 333, pi. 28, f. 14-16, 1847. (First, ed. 1845)- 

 Modiola appendiailata Philippi, Abb. u. Beschr. 2, p. 150, pi. 



r, f. I, 1846. 

 Lithodomus appejidiculatus ^&e\'e, Conch. Icon., 10, pi. 4, f. 



21, and biexcavatus Reeve, f. 22, a-b, '57. 

 Lithophagus bisulcatus TiaW, Bull. 37, U.S. N. M., p. 38,' 89. 

 Bistribution. — S. Carolina to Rio de Janeiro. Upper Oligocene 



(of Tampa) to Recent. Living at Cedar Ke^'s, Florida. 



aristata Billwyn 



Mytilus aj-istatus D\\\\\yn, Cat. Rec. Shells, i, p. 303, 1917. 

 Modiola caudigera Lamarck, An. .s. Vert., 6, p. 116, 1819. 

 Lithodomtis caudigcriis 'R.e^xe, Conch. Icon., 10, pi. 3, f. 16, 



1857- 

 Lithophagzis forjicatus Ravenel, Proc. Acad. Nat. Sci. Phila. 



fori86i, p. 44; Ball, Bull. 37, U. S. N. M., p. 38. '89. 

 Lithophaga aristata Ball, Tr. W. I. S., 3, pt. 4, ]). 800, '98 ; 



