82 NEW-YORK FAUNA — MOLLUSCA. 
(EXTRA-LIMITAL.) 
FAMILY CYCLOSTOMIDZ., 
ANIMAL without a collar, and with two tentacles eyed at their external bases. SHELL conoid, more 
or less elevated, with the aperture rounded, and with ils margin continuous. 
Genus Cyciostoma, Lam. Animal very spiral, with a proboscis-like head bearing two cylindrical 
tentacles, swollen at their tips, contractile and eyed at their external bases. Foot oblong, 
elongated. Pulmonary cavity communicating externally by a large fissure in the upper and 
anterior part of the mantle. Place of the male organ indicated by a large tentacular appendix 
on the right side, and reflected into the pulmonary cavity. Shell conoid, discoid or turreted, 
more or less elevated. Aperture circular, entire, and in the adult reflected. Opercle calca- 
reous, increasing concentrically : summit subcentral.° 
C. dentata. (Say, Ac. Sc. Vol. 5, p. 125.) Shell conic, cylindric, truncate at tip. Whorls 3-4, 
slightly convex, cancellate with fine regular subequal longitudinal and transverse elevated lines; 
superior edge fimbriated, with prominences extending over the suture; lip somewhat reflected ; 
umbilicus distinct. Color, rufous; revolving lines occasionally obsolete; lip white. Height, 0-4. 
Florida. 
C. cincinnatiense. (Lea, Am. Phil. Tr. Vol. 8, p. 229, pl. 6, fig. 62. A. sayana? Anthony.) 
Shell elevated in the form of a cone, smooth, shining, transparent, umbilicate. Whorls 6; apex 
obtuse ; margin of the lip reflected. Length, 0°22; diameter, 0-13. Cincinnati. 
FAMILY HELICINIDZ. 
ANIMAL with a collar; two filiform tentacles, with eyes at their external bases on tubercles. SHELL 
more or less globular ; aperture entire, semioval ; columella transverse and flattened ; opercle horny. 
Genus Heticina, Lam. Animal with a bilabiate muzzle; foot short, rounded, with a transverse 
furrow in front. Pulmonary cavity opening in front of the mantle by a large transversal 
furrow. Shell subglobular, slightly depressed, not umbilicated: spire low; columella callous; 
margin of outer lip acute, forming an angle at the base of the right margin. 
H. orbiculata. (Say, Am. Conch. pl. 46, fig. 1-3.) Subglobular; spire not very prominent, but 
more than convex. Whaorls five, obsoletely striated across, regularly rounded ; base of columella 
very slightly projecting into an obtuse angle; lip reflected. Color, pale greenish, yellowish or 
slightly reddish, margined above by a paler line; occasionally a pale revolving band on the body- 
whorl. Florida. 
H. fastigiata. (Iv. Des. terr. & fluv. shells, p. 14.) Whorls compressed, acutely carinated; beneath 
the carina, the elevated lines obsolete. Lip two-toothed; the lower conic, obtuse. Diameter, 0°35. 
Illinois. ; 
H. plicata. (Iv. 1. c. p. 14.) Inferior tooth compressed, and larger than, the other; duplicature of 
the labium emarginate near the tip. Closely allied to the preceding. 
H. occulta. (Ip. l.c. p. 15; Am. Conch. pl. 46, figs. 4, 6.) Whorls five, carinate, or with an 
acute shoulder, which is almost concealed on the spire by the suture, and almost obsolete on the 
body-whor!, which latter has faint revolving lines. Lip thick, a little reflected. Western States. 
