72 NEW-YORK FAUNA — MOLLUSCA. 



LlMNEA LINSLEYI. 



PLATE IV. FIG. 74. a. b. 

 (STATE COLLECTION.) 



Description. Shell ovate, subventricose. Whorls five, rounded, and rapidly attenuated to 

 the apex : suture deep. Aperture oblong-oval, longer than the spire. Pillar-lip with a 

 broad calcareous deposit ; the lower portion reverted, and partially covering the umbilicus. 

 Lip thin, forming a shoulder at its junction with the preceding whorl. Body-whorl towards 

 the margin of the outer lip, flattened as in megasoma, and impressed with deep incremental 

 stria? which are evident from within. 



Color. Epidermis chesnut, often obscured by a blackish subvillous pigment. 



Length, 0'25. Aperture, - 15. 



This shell has affinities of form with catascopium, and more especially with the variety 

 which is designated by Say as L. pinguis. That variety is, however, represented as having 

 a moderate suture, and the whorls nearly four. 1 have ventured to impose upon it a new 

 name, expressive of my obligations to the Revd. Mr. Linsley of Stratford, who furnished 

 me with the specimens from his neighborhood. 



LlMNEA COLUMELLA. 



PLATE IV. FIG. 75. 



(STATE COLLECTION.) 



L. columella. Say, Nich. Ency. Ed. Am. Vol. 4, No. 3. Jour. Acad. Nat. Sciences, Vol. 1, p. 14 ; Vol. 2, p. 167. 



L. macroslomus. In. Jour. Ac. Nat. Sc Vol. 2, p. 170. 



L. acuminata. Adams, Amer. Jour, of Science, Vol. 39, p. 374 (Young). 



L. columella, and var. chalybea. Gould, Invertebrata of Mass. p. 215, figs. 144, 145. 



L. id. Haldeman, Monograph of Limniades, p. 39, pi. 12, figs. 1, 15. 



Description. Shell ovate, ventricose, fragile, thin in texture, diaphanous : suture impressed 

 and conspicuous. Whorls four, with incremental lines crossed by minute spiral striae. Spire 

 narrow, acute, and much shorter than the aperture. Aperture very large, more or less 

 expanded. Pillar-lip with a thin film of enamel, not quite appressed anteriorly : it is so 

 much arched as to display a considerable portion of the interior of the shell. 



Color. Pale greenish, or straw-yellow. 



Length 0-5-1-0. 



This species has very much the aspect of a Succinea. Mr. Haldeman has very judiciously, 

 as I think, united two nominal species into one. It abounds from Canada to South-Carolina. 

 In this State, I have procured specimens from the locks at Schenectady, and throughout the 

 western district. 



