FAMILY HELICILLE — VITRINA. 25 



FAMILY HELICIDJE. 



Body elongated, twisted spirally, and distinct from the foot. Tentacula four, rarely two ; 

 the upper bearing the eyes. Shell closed by a fleshy collar. Generative organs united in 

 front. Vent near the breathing orifice. Shell globular, spiral, varying very much in its 

 form, and receiving the body more or less completely. 



GENUS VITRINA. Draparnaud. 



Body slightly spiral, with a fleshy collar surrounding the neck, and produced forward into a 

 sort of shield, and, with other retractile appendices, covering the shell. Foot separated by 

 a slight furrow. Shell very small, thin, transparent, fragile, and flattened, without an um- 

 bilicus. Aperture large, but its margin not tumid, and borne on the posterior part alone of 

 the animal. 



VlTRINA PELLUCIDA. 

 PLATE III. FIG. 42. A. B. —(STATE COLLECTION.) 



Vitrina pellucida. Deapaen. Hist, des Moll. p. 119, pi. 8, fig. 34-37. 

 Hetico Umax. Ferdssac, Method. Conch, pi. 29 ; Moll. pi. 9, fig. G. 

 Vitrina pellucida. Say, Long's Expedition, Vol. 2, p. 258. 

 V. id. Adams, Am. Jour. Sc. Vol. 40, p. 274. 



Description. Shell minute, ear-shaped, slightly spiral at its summit. Aperture very large. 

 Animal with its breathing and excretory orifices behind. Generative apparatus under the 

 right superior tentaculum. 



Color, greenish yellow. 



Greatest diameter, 0*25. 



In this country, the above species was first detected by Mr. Say, under stones and fallen 

 timber, near Coldwater lake, Lat. 48° 50' north. It has more recently been found in this 

 State by Mr. Adams, at Rogers's Rock, Lake George. 



Through inattention, the figures b. c. on the plate, are erroneously said to be of the natural 

 size. 



GENUS HELIX. Linneus. 



Animal with a head rather distinct, with four retractile tentacula enlarged at the end : a fleshy 

 collar closes completely the orifice of the shell. Foot large, oblong. Generative organs 

 as in the preceding genus. Shell very variable in its form, globular, fusiform, conoidal 

 or turreted. Aperture crescent-shaped, simple or toothed, oblique, broader than long. 

 Umbilicus open or concealed. From three to fourteen spiral turns. Usually dextral. 

 Fauna — Part 6. 4 



