1890.] 



NATURAL SCIEXCES OF PHILADELPHIA. 



187 



spiral lines become visible, mak- 

 ing the surface granulate ; tliey 

 are nearly obsolete on the body- 

 whorl, but usually distinct inside 

 the umbilicus and on the earlier 

 whorls. The spire is low, ob- 

 tuse ; sutures deeply impressed. 

 Whorls 6, slowly widening, the 

 inner three somewhat protruding 

 above the outer ; the last whorl 

 very convex above, obsoletely 

 angled on its earlier portion, be- 

 coming rounded, shortly but de- 

 cidedly deflexed in front. Aper- 

 ture very oblique, rounded-lu- 

 nate ; peristome expanded on its 

 outer margin, reflexed, blunt 

 and much thickened on the 

 basal and columellar margins. 

 Umbilicus deep, permitting one 

 to see to the apex, and funnel- 

 shaped. 



Alt. 22, greater diam. 42, lesser 

 37 mm. ; width of umbilicus 8 

 mm. ; oblique alt. of mouth 

 (meas. outside perist.) 21, width 

 21 mm. 

 Another specimen measures : Alt. 22, diam. 45 mm. 



Habitat, Liu-Kiu Is. (Dr. Ruschenberger). 

 This is a very solid, heavy form, apparently belonging to the 

 group of H. pallasiana Pfr. but very different from that species in 

 its much more convex whorls, deeper suture, more broadly ex- 

 panded umbilicus, and in the rounded body-whorl, the earlier part 

 of which is very acutely carinated in H. jxdlaslana. There are four 

 specimens befoi-e me, one of them about half grown, the others adult. 

 The young shell is very obtusely angled at the periphery ; the strite 

 are minutely granulated. The embryonic shell is large, about one- 

 fifth the diam. of the adult, composed of about 2f whorls, of which 

 the outer lA are finely, distinctly granulate, the inner ones having 

 low, curved, radiating little folds. The termination of the embry- 

 onic shell is marked bv a distinct line. 



