AS Trochus obeliscus: Shell imperforate, solid, thick, strictly conical, the spire more or less attenuated above, the apex acute; color yellowish or grayish, more or less mottled and marbled with green or brown, base white, green or brown; whorls 12-14, the upper ones slightly exserted and plicate, tuberculate or undulating at the sutures, the folds or tubercles obsolete on, the lower whorls; upper whorls encircled with one or two spiral series of small tubercles or beads, which are increased to about five series on the middle whorls; last whorl beaded, but smoother than the preceding, or radiately finely wrinkled, or nearly smooth, angulate at the periphery; base flat, concentrically lirate, the ribs smooth, wide, separated by shallow grooves, obsolete toward the outer margin; aperture transverse, very oblique, sub-triangular, the outer wall grooved within, the basal margin straight, not concave in the middle, deeply notched at its junction with the columella, sculpture inside with revolving acute plicae, corresponding to the lirae which revolve around the central area outside ; columella very short, with a very strong acutely carinated spiral fold. Alt. 75, diam. 75 mill.

AS: Trochus obeliscus: Indian and Pacific Oceans; Samoa, Fiji and Philippines, New Caledonia; N. Australia, etc. Singapore.

Trochus coerulescens: Form very slender; spiral beading sub-obsolete; color dark greenish, obliquely strigate with brown; base green, brown or yellowish ; outer wall of aperture (in the specimens I have seen) not grooved within ; other characters as in the Tectus pyramis / Trochus obeliscus.

AS Trochus obeliscus: I believe that this is the T.pyramis of Born; but since there is some doubt about it, I have followed the precedent of Dr. Fischer in adopting Gmelin's name.