Shell large, stout, with a chalky external layer under a thin pale yellow epidermis, and an internal porcellanous white layer; a strongly curved and recurved canal; four columella plaits, nearly obsolete in the adult; the surface finely spirally striated; earlier whorls with the suture appressed and numerous (on the fourth whorl about 25) small short transverse riblets mounted on the periphery ; outer lip sharp; throat pure white; pillar lip merely glazed, exterior spotted with squarish brown spots with less regularity of size and position and more distant than in S. junonia; whorls six beside the nucleus, fully rounded, somewhat irregularly coiled. Lon. of shell, 119.0 mm; of last whorl, 100.0 mm; of aperture, 8S.0 mm. Max. diameter of shell, 52.0 mm. Nucleus small, of one and a half concave whorls, with the acute initial point central, rising above the margin of the concave, which is formed by the sharp posterior edge of the first post-embryonic whorl; this whorl is sculptured with very low flat striated transverse riblets with narrower channelled interspaces, extending clear across the whorl and both crossed by about eight distinct spiral threads between the two sutures ; after the first turn the transverse bands become narrower, the interspaces about equal to them, and the spiral threads wider and flattened so that a fine and exceedingly elegant trellising is the result. The second whorl begins to be spotted with squarish brown spots with fainter edges, of which seven series appear at the end of the second turn ; interior yellowish white with four sharp plaits on the pillar, very oblique, and growing stronger backward ; epidermis smooth, thin, not polished ; suture very closely appressed. Lon. of this young shell, with nucleus and two whorls, 12.0 mm ; of second whorl, 11.0 mm ; max. diam., 5.0 mm.

Scaphella robusta Dall, 1889 DEEP WATER
Distribution: Texas, Florida. Size: 112 mm
Description: Color straw yellow with rows of grayish-brown periostracum; shape broadly ovate; sculpture of strongly convex whorls that are distinctly shouldered; shoulders of body and penultimate whorls with a spiral row of nodules on periphery of each whorl; body whorl almost 2A length of shell; spire acute; aperture long and broad.
Habitat: On sandy mud bottoms; in deep water to depths from 218 to 695 m (715 to 2280 ft).
Remarks: Rare. Specimen in photograph in Tunnell collection; collected off SPI in shrimp trawl at about 244 m (800 ft). Compare with Dalls (1889b) holotype. See Clench (1946, 1953); Abbott (1974).

Description. Shell large, reaching about 112 mm. (4,75 inches) in length, fusiform and rather solid. Whorls seven and rather strongly convex. Color a straw yellow with about ten spiral rows of square dark brown spots (holotype). Aperture elliptical and somewhat lengthened. Spire acute and moderately lengthened. Suture slightly indented. Outer lip thin, parietal wall thinly glazed. Columella strongly arched and supporting three weak plicae. Siphonal canal broad and strongly arched dorsally. Sculpture; nuclear whorl smooth, remaining whorls with numerous fine incised lines which persist to the body whorl. From the fourth to the sixth whorl there is a series of rather strong axial costae at the whorl shoulder. Nuclear whorl small with the calcarella and first whorl somewhat extended.
Remarks. (See also under S. cuba). A large species which does not appear to be very close in its relationships with the other members of this genus. The records of Dall (1889), p. 1.53) and our own (1940, p. 88) are open to question as all were based upon immature specimens.

This fine and remarkable species is peculiarly distinguished by its chalky outer layer, under a pale epidermis, which becomes eroded, like that of a freshwater shell. The form of the nucleus, if the hypothesis of a membranous embryonic first shell be admitted, would be due to a calcification which did not extend to the dome of the membrane, while the acute initial point of the calcified part may be supposed to occupy the vicinity of the pillar in the soft shell. The posterior margin of the first post-embryonic whorl might easily be rounded off by erosion, when the solid nucleus within after a little wear would put on quite a different appearance. The pattern of coloration, resembling S. junonia and S. dubia, also resembles that of young Conus floridanus, Conus mazei Deshayes, and other not related archibenthal species. The pillar is more flexuous than in either of the other species. The riblet sculpture resembles not only that of S. dubia and S. gouldiana in a general way, but also that of the fossil S. mutabilis perhaps the precursor of all the Gulf species.

Caribbic and Gulf of Mexico.