36 HELIClDiE. 



and excavated around the columella ; aperture obliquely oval ; 

 peristome thickened within ; columella much dilated and 

 appressed. H. alauda, Fer. Cuba. 



Histrio, Pfeiffer, 1854. TJncharacterized. H. Dennisoni, Pfr. 

 Cuba. 



Jeanner-etia, Pfeiffer, 1877. Uncharacterized. H. Parraiana^ 

 d'Orb. 7 sp. Cuba, Porto Rico. 



Dialeuca, Albers. Imperforate, turbinately globose ; five 

 whorls, the last obtusely angulate ; aperture obliquely rounded ; 

 peristome simple, sharp ; columella intrant, oblique, wide, flat- 

 tened above. H. nemoraloides^ C. B. Ad. (xcv, 65). Jamaica. 



OXYCHONA, Morch, 1852. Imperforated, trochiform ; last whorl 

 carinated with flattened base; peristome simple, sharp, outer lip 

 inflected in the middle, columellar lip thickened. H. bifasciata^ 

 Burrow (xcv, 74). Brazil. 



POLYMITA, Beck, 1837. (Phaedra [pt.], Albers, 1850.) Shell im- 

 perforate or perforated, globular, shining ; spire small and short ; 

 whorls four or five, the last very large and rounded ; apei'ture 

 rounded ; peristome simple, obtuse, the extremities joined by a 

 transparent callus ; columella oblique, widely dilated above. H. 

 picla, Born (xcvi, 80); Cuba. 5 sp. Cuba. 



Cysticopsis, Morch, 1852. (Parthena, Albers, 1S50, partim.) 

 Shell imperforate, globose, shining; whorls convex, the last ven- 

 tricose ; aperture large, rounded ; columella short, vertical, a 

 little dilated above ; peristome simple. H. Cubensis, Pfeiffer, 

 (xciv, 17). 20 sp. West Indies. 



Praticola^ Strebel and Pfeffer. Shell globular, irregularly 

 plaited, aperture expanded, thickened internally, concealing a 

 part of the narrow umbilicus. Mexico. H. griseola, Pfr., and H. 

 Berlandieriana^ Moric.,ai'e examples. 



Pelia, Albers, 1860, Shell imperforate, depressed, lenticular, 

 thin, with concentric lineated lines, acutel}'^ carinate ; whorls five, 

 slightly convex, the last with convex base, impressed in the 

 middle; apertui^e subrhombic ; peristome simple, acute. H. 

 spirulata, Pfeiffer. Central America. 



Plagioptychia, Pfr., 1855. Umbilicus narrow or covered, 

 depressed suborbicular, thin, small, spire scarcely elevated, 

 obtuse ; whorls four-and-a-half, the last suddenly deflected and 

 constricted at the aperture ; aperture subhorizontal, elongate- 

 lunate ; peristome thin, margins approaching, the basal with a 

 dentiform plica. H. loscodon, Pfr. (xcv, 70 . 19 sp. Hayti, 

 Bahamas, etc. 



Hemitrochus, Swainson, 1840. (Phaedra [pt,], Albers, 1850,) 

 Shell imperforate or perforate, globose, shining, spire short, 

 whorls 4-5, the last large, deflected at the aperture; aperture 

 contracted, subvertical, rounded - lunate ; peristome simple. 



