182 HELIX. 



panded and reflexed, its margins subcon verging, equally curved, 

 the lower appressed in the middle, not impressed at the insertion, 

 callous, half covering the umbilicus. Diam. 23, alt. 14 mill. 



Ins. Gomera, Canaries. 



A species allied to H. planorbella, but without trace of angle on 

 the body-whorl. It has been found only in a fossil state. 



H. PAIVANA Morelet, 1864. Unfigured. 



Umbilicate, orbicularly depressed, obliquely granulate-striate, 

 yellowish or greyish brown, with four interrupted bands; suture 

 impressed ; whorls 5, slightly convex, the last carinate above, de- 

 flexed anteriorly, turgid below; aperture very oblique, transversely 

 oval, expanded slightly within, columellar margin dilated ; umbilicus 

 half covered. Diam. 24, alt. 11 mill. (Morelet.) 



Ins. Gomera, Canaries. 



This is not the paivana of Lowe (1861) which=:.ff. modesta Fer. 

 On account of this preoccupation, Mabille proposes the name 

 paivanopsis for this species. 



"The H. paivana is a rather depressed but obtuse shell there be- 

 ing no indications of a regular keel ; its spire is only slightly raised, 

 but somewhat blunt and dome-shaped ; and its umbilicus is partially 

 visible, it being only half closed-over (or perhaps rather more) by 

 the reflexed peristome. It is somewhat thin in substance, tumid 

 beneath, and of a yellowish brown hue, paler below but ornamented 

 with four narrow and regularly interrupted darker bands, which 

 give a somewhat freckled appearance to the whole upper side ; and 

 the surface is beset with coarse tubercles (which become obsolete 

 toward the nucleus, and gradually disappear on the umbilical area), 

 caused by the breaking-up of the densely-packed oblique lines of 

 growth." ( Wollaston.) 



H. QUADRICINCTA Morelet, 1864. PI. 53, figs. 24-26. 



Umbilicate, depressed, lenticular, acutely carinate, costulate or 

 plicate striate, yellowish corneous, with four castaneous bands, one 

 peripheral, another below, the balance upon the upper surface; 

 whorls 5, slightly convex, the last anteriorly deflexed, base subturgid, 

 aperture very oblique, transverse oval ; peristome thickened, white, 

 outer margin expanded, columella dilated, appressed, subdentate; 

 umbilicus small, pervious, half covered. Diam. 19, alt. 8 mill. 

 (Morelet.) 



Ins. Gomera, Canaries. 



