21 



A small, very pellucid shell, somewhat like IT. eleclrina and 

 lucida, but more globular. 



Helix gradata. Testa parva, planorboidea, tenuis, nitida, 

 rufo-viridis, luteo radiatim variegata, supra depressa, infra aceta- 

 buliformis : spira anfr. 5 convexis, intra umbilicum angulatis, 

 oblique et confertim striatis et cum striis interruptis volventibus 

 decussatis ; ultimo subangulato, versus aperturam deflexo ; sutura 

 canaliculata : apertura obliqua, subcircularis ; labro acuto, ad um- 

 bilicum reflexo. Lat. |, alt. 4 poll. Hab. Tongataboo. 



Shape and size of H. striatella, Anthony, but has the umbili- 

 cus broader, deeper, and more shelving. 



Helix fornicata. Testa parva, planorboidea, tenuis, dilute 

 rufa, supra convexiuscula, infra concava, oblique ordinatim et 

 confertim costato-striata : spira anfr. 4 convexis ; ultimo ad peri- 

 pheriam rotundato ; sutura profunda : apertura transversa, rotun- 

 dato-elliptica. Lat. ^, alt. T V poll. Hab. Kauai, Sandwich Is- 

 lands. 



A small, dome-shaped shell, marked like H. striatella, but 

 more like H. indentata, in the form of the spire. 



Helix rubiginosa. T. orbicularis, depressa, ferrugineo-cornea, 

 fusco tessellata, oblique costato-striata, late umbilicata ; spira anfr. 

 6 arete volutis ; sutura impressa : apertura subrecta, lunata ; 

 labro simplici ; lamella unica secundum anfractum penultimum 

 volvente. Lat. ^, alt. 5 ^ poll. Hab. Kauai, Sandwich Islands. 



Larger than the other checkered shells of this group ; like H. 

 striatella, Anthony, in form, size and sculpture, or like H. radi- 

 ata, Mull., as to coloring. 



Helix d^dalea. Testa parva, discoidea, rubro-castanea, 

 fusco tessellata, costellis radiantibus acutis confertis scabra, sub- 

 tus acetabuliformis : spira anfr. ad 6 arete volutis, duplo altiori- 

 bus quam latis, ad peripheriam rotundatis, infra haud planulatis : 

 sutura impressa : apertura angusta, verticalis, lunata ; fauce 

 lamellis 9 volventibus instructa, quorum 4 ad anfractum penulti- 

 mum, uno ad columellam, 2 ad basim, 3 ad labium dispositis. 

 Alt. ^ lat. Jo poll. Hab. Taheiti, Matea. 



Size and color of H. contorta, Fer. ; but the whorls are more 

 numerous and compact, and there are twice as many lamellae on 

 the penult whorl. The umbilicus is similar in form to that of the 



