36 TROCHUS. 



between eacli of the scallops, so that the periphery, when viewed 

 below, appears doubly crenulated ; coluraella sharp, contorted ; 

 aperture trapezoidal ; color flamed alternately darker and paler 

 brown. (Gould.} Alt. 15, diam. 21 mill. 



Singapore (Phil. Acad. Coll.). 



T. bicrenatus GOULD, Proc. Bost. Soc. Nat. Hist., iii, p. 106, 1849. 

 U. S. Expl. Exped., xii, p. 175, t. 13, f. 221. 



Two specimens of this species marked "Singapore" are before 

 me. They differ from the type as figured and described by Dr. 

 Gould in various characters. One of them is figured on PI. 12, 

 figs. 68, 69. The whorls are planulate, spirally granose-lirate, the 

 line about 8 on each whorl, but sometimes nearly obsolete; the 

 lower third of each whorl is strongly, regularly folded, the folds 

 scalloping the periphery ; the base is flat, very finely, subobsoletely, 

 concentrically granose-lirate ; the coloration above consists of fine 

 close obliquely descending narrow red lines on a white ground ; be- 

 neath of radiating narrow lines. Alt. 17, diam. "22 mill. 



T. IGNOBILIS Philippi. PL 12, figs. 82, 83. 



Shell elevated conical, whitish, painted with rufous radiating 

 flexuous lines ; whorls 6 to 7, planulate, above with four spiral fur- 

 rows, the last. obtusely angulated ; base flattened, with 6 to 7 con- 

 cbntric sulci ; center false-umbilicate ; coluinella contorted above; 

 aperture rhomboidal ; outer lip with four revolving line within, 

 parietal wall with one, the base with three spiral line, ending in 

 denticles ; columellar edge four toothed. 



Alt. 18, diam. 17 mill. (Philippi) 



Sandwich Is. 



1. igaobilis PHIL. Zeitschr.f. Mai. 1846, p. 102. Conchyl. Cab. 

 p. 98, t. 16, f. 5. 



A species unknown to me save by Philippics description and 

 figure. It may, perhaps, be allied to T. sctibrostis, Phil. 



T. TRICATENATUS Reeve. PI. 43, figs. 7, 8. 



Shell excavately umbilicated, rather obtusely conical, solid, some- 

 times fulvous white, flamed with rose, sometimes greenish flamed 

 with ash-olive ; whorls narrowly three-chained at the upper and 

 lower parts, encircled around the middle with three rows of strong 

 grains, basal margin rounded; base rather convex, closely serially 

 grained, sparsely spotted. (Reeve.) 



Habitat unknown. 



