HELIX. 91 



H. TUMULUS, Gould. PI. 18, figs. 71-73. 



Moderately umbilicated, solid, roughly subobliquely striated, 

 yellowish ; whorls 6-7, a little convex, with angulated periphery,, 

 compressed towards the aperture. Diam. 10 mill. 



Viti Is, 

 H. ABROCHROA, Crosse. PI. 18, figs. 74, 75. 



Very widely umbilicated, thin, diaphanous, a little shining, 

 smoothish, scarcely obliquely striulate, yellowish corneous, suture 

 margined ; whorls 5, moderately increasing, the last not descending, 

 very acutely carinated, base somewhat convex, angulated around 

 the umbilicus. Diam. 10 mill. 



Ins. Viti-Levu.. 

 Var. PSEUDOPLANORBIS, Mousson. 



Spire higher, base more flattened and umbilicus narrower. 



H. CRESSIDA, Gould. PL 18, figs. 76-78. 



Widely, deeply umbilicated, solid, closely, sharply striated r 

 shining, with coalescing fasciations of chestnut and yellowish green ; 

 whorls 5, scarcely convex, the last acutely carinated, base sub- 

 planulate. Diam. 17*5 mill. 



Ins. Samoa, Tahiti, Eaiatea. 



H. FALLENS, Pease. PL 18, fig. 79. 



Umbilicus narrow, shell rather solid, obliquely roughly striated,, 

 scarcely shining, yellowish white, with two submedian reddish 

 chestnut bands, the lower one wider, suture with narrow margin ; 

 whorls 6, slightly convex, slowly increasing, the last not deflected 

 in front, the acute keel whitish. Diam. 16 mill. 



Tahiti and Moorea, Society Islands. 



Pease described it as a variety of H. trochiformis, Fer. Garrett 

 considers it distinct (Jour. Philad. Acad., ix, 25). Varieties have 

 wide median bands, or pale honey yellow with narrow, often mar- 

 ginal bands, or uniform whitish or yellowish-white, or dark chestnut 

 color, with white keel and suture. 



H. SWAINSONI. Pfr. PL 18, fig. 80. 



Moderately umbilicated, thin, pellucid, subarcuately rugosely 

 striated, greenish fulvous, with two chestnut lines ; whorls 5,. 

 depressed, the last acutely carinated. Diam. 16 mill. 



Tahiti; feleliu, 



H. exclusa, H. scuta and H. lenta, Pease, are synonyms, the two- 

 latter are MSS. names. 



