214 CERION, GROUP V. 



Length 17-30 mill. Florida Keys; Gun City, Jlahrnnas. 



Pupa maritima }' PFR., Monogr., iii, p. 539 GOULD in Binney's 

 Ten-. Moll., ii, p. 316, Pupa incana A. BINNEY, Ten-. Moll. U. S., 

 i, p. 109, name only; iii. p. 318, as a synonym of P. maritima (1851 ); 

 iii, pi. 68 (1857). LEIDY, t. c., i, pi. 15, f. 2-4 (anatomy). PFR., 

 Monogr., iv, p. 657 ; vi, 289, with var. variegata, based upon Bin- 

 ney's pi. 70 (error for 79), f. 17 (1868). W. G. BINNEV, Terr. 

 Moll., iv, p. 141, and \-AI: fasciatu p. 206, pi. 79, f. 17 (1859); Land 

 and F. W. Sh. of N. A., i, p. 247, f. 430. Pupa detrita Shuttle- 

 wortli, PFK., Malak. HI., i, p. 205, pi. 3, C. 9, 10 (1854). SOWB., 

 C. Icon. pi. 3. f. 17. Strophia incnna Binn., TRYON, Amer. Journ. 

 of Conch., iii, p. 308, pi. 15, f. 19 ; Mon. Terr. Moll. U. S., p. 135, 



pi. 15, f. 19 (copied from Terr. Moll., iii, pi. 68, lower fig.) W. 



G. BINNEY, Terr. Moll., v, p. 220, pi. 68, and fig. 126; Man. Amer. 

 L. Shells, p. 419, f. 462, 463 (jaw and teeth), 464. 465 (shell). 

 MAYNARD, Contrib. to Science, i, p. 78. f. 13, pi. 7, f. 20, 20a. 

 SIMPSON, Proc. Davenport Acad., v. p. 68 Cerion incanum Binn., 

 PILS. and VAN., Proc. A. N. S. P., 1896, p. 320. PILSBRY, Nau- 

 tilus, xii, p. 26 (Gun Cay) C. incanum saccJiarimeta Blanes, PILS. 

 and VAN., Proc. A. N. S. P., 1898, p. 477, f. 5. 



This species is generally smaller than C. maritimum sublcevigatum 

 of Cuba, and it has a longer cone with more obtuse apex. C. in- 

 cunoides of Turk's Island is very similar, and distinguished chiefly 

 by its decided excavation behind the columellar lip, the reflexed edge 

 of which is pushed forward in the middle. 



At Key West, the type locality, C. incanum occurs abundantly 

 between the salt ponds and the northern shore. The shells are 

 white, flesh-tinted or bluish, with several apical whorls light brown. 

 Frequently there are a few rather ill-defined livid spots, more numer- 

 ous on the cone. The variation in size is great: 30x11; 25x8^; 

 22x10; 17x7| mill. The last whorl is often irregularly wrinkled, 

 almost subcostulate. Figures 48-50 are from Key West examples. 



SUGAR-LOAF KEY. Var. saccharimeta ' Blanes ' P. and V. (pi. 

 29, figs. 52, 53). The specimens are chalky-white with a blue tint, 

 and corneous apical whorls, the next whorl being very finely but dis- 

 tinctly rib-striate. There are irregularly developed, low and wide- 

 spaced riblets on the last one or two whorls. Terminal cone more 

 tapering than in normal incanum. Size variable, from 38x13^ to 

 28x1 H mill. The specimens from this key show well-marked racial 

 divergence. 



