Cerion (Strophiops) rhyssum Dall, 1905

Original Description

"CERION (STRIOPHIOPS) RHYSSUM n. sp.

Plate XII, Figs. 4, 6.

     Fossil in the æolian rock of a small unnamed key south of Reids Cay, Middle Bight, Andros Island, at Station 14.

            Shell large, heavy, solid, with a short parietal tooth, the axial tooth absent or obsolete; axis a hollow cylinder with a small umbilical perforation in the adult; whorls 10-11, the nepionic whorls at first smooth and polished, then delicately axially striated; form cylindrical with a short apical cone, sometimes much depressed; sculpture of the adult whorls of about 17 rather sharp, slightly oblique ribs, with wider interspaces, the basal whorl attenuated and more finely wrinkled axially below; there is no basal cord or spiral striation; peristome slightly thickened and continuous. The color is, of course, grayish white with traces of brown in the throat. Measurements of the two most contrasted specimens, in millimeters are:

Height.             Max Diameter.              Height of last whorl.

33                     16.0                              17        

26                     17.5                              16

            This species belongs to Maynard's section Pinguitia and seems most closely related to C. dimidiatum Pfr., of which the short form is C. proteus Gundlach; a Cuban species found at Gibara."

 

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