Cerion fordii Pilsbry & Vanatta, 1897

Original Description

"Cerion fordii P. & V. Figs. 1, 2.

Shell cylindrical, the latter three whorls of equal diameter, those earlier forming a rather short, obtuse cone. Wholrs 10 to 10½, earlier two white, smooth, the following finely striated, striae or riblets evenly spaced though of variable closeness, in number 32 to 45 on the last or next to last whorl, not splitting or more numerous on the base of the shell, which is rounded, not compressed; umbilical chink short, subperforate. Color: longitudinally mottled with brown, ochre and snow-white; sometimes uniform white.

Aperture vertical or with the base somewhat advanced; parietal tooth about the median, high, long and strong, extending backward about four millimeters. Columellar foldvery slight, situated high. Peristome reflexed, its face much thickened; light brown or whitish; parietal wall generally heavily calloused.

Alt. 30, diam. of penult. Whorl 12, alt. aperture 12½ mm.

Alt. 27, diam. of penult. Whorl 12, alt. aperture 10½ mm.

Alt. 28½ diam. of penult. Whorl 11, alt. aperture 11 mm.

Typical C. fordii exactly resembles externally a coarsely sculptured form of C. Dallii from Inagua; but it has the internal armature of Strophiops or Maynardria. It is a coarser, larger shell than C. eximeum of Cat Island and New Providence, with far stronger development of peristome and teeth and more interrupted strigation. C. fordii has not the raised ledge across the parietal wall of C. glans varium, from New Providence, has stronger peristome and teeth, and is larger.

The pure white form of C. fordii resembles C. abacoense, but is less stout in the average, has a liver-tinted mouth and lip, and the parietal tooth is notably longer and stronger.

Several hundreds of this species were obtained by Mr. John Ford from a barrel of shells from the Bahamas, exact island unfortunately unknown. On comparison with the nearly complete series of Cerion in the collection of the Academy it is evident that a new polymorphic species is before us, probably from an island or region of an island hitherto unexplored for this genus. Both the striate and smooth forms occurred either white or strigate, and so far as we an judge in nearly equal numbers. Transition forms are fully represented, though probably 95 per cent. of the specimens are either the one or the other." (Pilsbry and Vanatta, 1897:365-366).

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