202 TURBO. 



upper angle sometimes separated from body-whorl, and projecting, 

 base rounded, columella excavated at umbilicus. Alt. 40-50 mill. 



-iVe ? v Ca ledon ia ; Sa i 1 div ich Is . 



Operculum circular, with 5 whorls ; outside granulose, green or 

 olivaceous at centre, yellowish at margins. 



Sculpture less sharp than in the following form, and color greener. 



The synonyms are T. disjunctns Anton, T. continnus Phil., and 

 T. articulatus Reeve, (pi. 45, fig. 98) T. elegans Phil., = T. radiatus 

 Rve., (pi. 46, figs. 5, 6) is a form somewhat intermediate between 

 typical intercostalis and ticaonicus Reeve. 



T. TICAONICUS Reeve, 1848. PL 47, fig. 22 ; pi. 43, fig. 51. 



Shell ovate-conic, perforate, solid, dirty white or greenish, radiate- 

 ly flammulate above and maculate below with black or brown ; 

 whorls 6, convex, slightly flattened 'below the subcanaliculate sut- 

 ures, sometimes subcarinate, spirally sculptured with inequal lira?, 

 the intervening furrows sharply squamose with stria? of increment ; 

 aperture round, produced into a projecting angle posteriorly and 

 frequently disconnected from the body-whorl, white and pearly with- 

 in, rounded or slightly produced below; outer lip crenulate, colu- 

 mellar arched, excavated at the narrow umbilicus, which is some- 

 times subimperforate. Alt. 50-60 mill. 

 Philippines; New Caledonia; Seychelles; Madagascar; Singapore^ etc. 



Operculum (pi. 60, fig. 47, 49,) with four whorls and subcentral nu- 

 cleus ; outside very convex, deep green, olive or brownish in the 

 centre, lighter toward the margins, all over except side of increment 

 finely granulose, and with a radial sulcus marking the limit of the 

 margin of increment. The prominent character of the operculum 

 in this species, as well as in T.foliaceus etc., is the manner in which 

 the outer layer of calcareus matter overlies the granulose surface 

 below, with an obvious sulcus at their junction. PI. 60, fig. 38, is 

 the operculum of the form known as T. tumidulns Rve. 



The following are synonyms: T. radiatus Kiener (in part), T. 

 tumidufus Reeve. This species is closely related to T. intercostalis 

 Mke., but differs in color, in the greater prominence of the ribs, and 

 in the operculum. My description and figure of the operculum of 

 ticaonicus are drawn from alcoholic specimens containing the animal. 

 T.foliaceus Phil, is also allied, and has similar operculum, but has 

 much more conspicuous incremental lamella?. The umbilicus is in- 

 differently perforate or closed, sometimes rather wide, and the 

 variation in sculpture is considerable. T. pulcher Reeve is separated 

 from this species principally because, according to Sowerby, its oper- 

 culum is different. I suspect however that he is mistaken in this, 

 and that it will prove to be the same; pulcher is the prior name. 



