Terrestrial Operctdate Mollusca from Trinidad, 24e7 



2700 feet. The animal has a rather elongate grooved foot 

 Lingual teeth 00.2.1.2.00: central tooth broad, simple; inner 

 lateral broad ; outer lateral broad, denticulated on the reflexed 

 edge ; uncini numerous, slender, curved at the tip. The lingual 

 dentition is thus shown to differ considerably from that of Ct/clo- 

 phorus. While the central and lateral teeth present a certain 

 resemblance to those of Cyclophorus, the uncini remind one of 

 Trochns, Nerita, and especially Helicina. The teeth of Adam^ 

 siella aripensis also resemble those of Cistula pupi/ormis, which 

 I have examined ; but in the latter there are no uncini. 



The shell of the present species is occasionally found without 

 its spire having suffered the usual slight truncation. 



Helicina zonata, n. sp. 



Shell subglobose-conic, thin, smooth, whitish, bright straw- 

 coloured or pinkish ; suture with a chestnut or red band which 

 becomes quite obsolete on the last whorl, and sometimes a 

 broader yellow or pinkish band on the last whorl ; spire conic, 

 mucronate; aj)ex deep red; whorls 5, convex, rather carinate, 

 flattened beneath ; aperture oblique ; columella terminating 

 in an indistinct knot dilated backwards into a thin circum- 

 scribed callus; peristome thin, white, expanded and reflected. 

 Operculum rather shelly, deep blood-red, except at the nu- 

 cleus and extreme margin, which are horn-coloured diapha- 

 nous. Height 0-27 inch, greatest breadth 042 inch. 



Lingual teeth 00. 3 . 1 ,3 .00 : central subquadrate, narrowed at 

 the base; 1st lateral subopaque, subtrapeziform, with the outer 

 corner much produced ; 2nd lateral subopaque, elongate, strongly 

 curved outwardly ; 3rd lateral broad, convex, glossy, denticulate 

 on the reflexed edge ; uncini numerous, slender, with the curved 

 tips finely denticulate. The peculiarities of the lingual dentition 

 of Helicina would seem to have been overlooked. The numerous 

 uncini and the subopaque trapeziform laterals remind us strongly 

 of Nerita, and would seem to give some support to the idea of 

 the close relationship of these genera — an idea which is further 

 supported by the resemblance of the shells of the two genera. 



Helicina barhata, n. sp. 



Shell globose-turbinate, thin, smooth, zoned with about three 

 chestnut or red bands, covered with a hairy periostraca ; spire 

 depressed-conic ; whorls 5, convex, flattened beneath ; aper- 

 ture oblique, semilunar; columella terminating in an indis- 

 tinct knot dilated backwards into a thin callus; peristome 

 narrowly expanded; right margin slightly sinuate above. 

 Operculum thin, concave, pale, diaphanous, blood red towards 



