TROCHUS. 19 



102, T. alhis Phil. Conch. Cab. ii, p. 217, t. 32, f. 7. T. senatorius 

 Phil., Conch. Cab. ii, p. 324, t. 46, f. 7. 



The T. alt us of Philippi is doubtfully placed here. It has more 

 acutely earinated periphery than any actangulus I have seen. I 

 have copied Philippi's figure on PI. 9, fig. 96. This species is the 

 type of (i ray's group Roch'nt. 



Submenus ( 1 .\ IIDIXALIA, Gray, 1840. 

 T. viKd.vrrs Gmelin. PL'S, figs. 43, 44. 



Shell imperf.irate, conic-pyramidal, solid, white, above longitudi- 

 nally broadly ilannnulated with red; spin- somewhat attenuated 

 and concave on its upper portion, then slightly convex, the sutures 

 'linear, whorls nearly planulate, apex acute; sculpture of spire con- 

 sisting of spiral prominently beaded line, about eight on each whorl; 

 whorls 10, the last carinated at the periphery; base plano-concave, 

 indented in the center, finely, densely lirate, the lirse minutely beaded, 

 red, articulated with white, the interstitial furrows white; aperture 

 snbrhomboidal, denticulate within the base ; columella short, oblique, 

 ending in a tubercle below, simply entering, not plicate, above, 



Alt. 4-"), diam. 40 mill. 



Indian 0.; Red Sea. 



T. virgatus GMKL., Syst. Nat., xiii, p. 3580. PHILIPPI, Conchy I. 

 Cab., p. 4, t. 1, f. 4, 5. REEVE, Conch. Icon., f. 69. FISCHER, Coq. 

 Viv., p. 97, t. 27, f. 1; t. 28, f. 1. 



The plano-concave finely lirate base, simple columella and tooth- 

 less aperture at once separate this species from other Trochids. 



Subgenus TECTUS Montfort, 1810. 



Tectus MONTF., Conch. Syst. i, p. 187. Pyramis SCHUMACHER, 

 Esaai d'nn nouv. Syst. Vers test., p. 232, (1817.) 



T. OBELISCUS Gniclin. PI. 2, figs. 13, 14. 



Shell im perforate, 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 tuber- 

 cles 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 radiatelv finely wrinkled, or nearly 



