68 NEW-YORK FAUNA — MOLLUSCA. 



LlMNEA FRAGILIS. 



PLATE IV. FIG. 68. 



(STATE COLLECTION.) 



Helix fragilis. Lin. L. elodes. Say, Journ. Acad. Vol. 2, p. 169; Am. Conchol. pi. 31, fig. 2. 

 L. elodes. Gould, Inverteb. Mass p. 221, figs. 146, 147. Adams, Am. Journ. Vol.40, p. 268. 

 L. fragilis. Haldeman, Monog. Limn. p. 30, pi. 6, figs. 1-11, p. 53 ; pi. 15, fig. 1. 



Description. Shell oblong-conic, gradually acuminated. Whorls six, convex, with trans- 

 verse lines, frequently marked with irregular elevated reticulations. Suture rather deeply 

 impressed. Aperture generally shorter than the spire. Pillar-lip with an angular deposit of 

 enamel. 



Color. Brownish tinged with yellowish, or amber-colored ; occasionally with a dusky 

 epidermis. Animal dusky, dotted with yellow. Tongue spoon-shaped: mouth margined 

 in front with a black horny plate. 



Diameter, 0-1-0- 3. Length 0-6 - 0- 9. 



One of our most common species, and referred by Mr. Haldeman, after a direct comparison, 

 to the L. fragilis of Europe. Ranges from Canada to Pennsylvania, and to the Pacific 

 westward. 



LlMNEA UMBROSA. 



PLATE IV. FIG. 76. 



(STATE COLLECTION.) 



Limneus clongatus. Say, Journ. Acad. Vol. 2, p. 167. 



L. umbrosa. Id. Am. Conchol. pi. 31, fig 1. 



L. umbrosa. Adams, Am. Journ. Science. Vol. 40, p. 268. 



L. idem. Haldeman, Monograph Limniades, p. 24, pi. 7, figs. 1-8. 



Description. Shell elongated, ventricose. Whorls six, slightly convex. Surface with 

 numerous minute spiral lines. Suture oblique, with little depth, but well marked. Spire 

 slender : apex acute. Fold on the columella not well marked. Aperture wide, nearly straight 

 on the inside, wide anteriorly, less than half the length of the shell. Body-whorl above 

 longer than half the entire length, often marked with reticulated lines forming facets as in 

 the preceding species. 



Color. Corneous, tinged with red or reddish brown. Margin of the lip lighter. Occasionally 

 the surface with light longitudinal lines. 



Length, 1'3; of aperture, - 7. 



This species occurs from Canada to Illinois. The first name imposed by Say having been 

 preoccupied, he changed it to that which it now bears. 



