LIMN^A. 49 



263 ; Am. Conch. VI, pi. 1, f. .5 ; ed. Binn. 66, pi. Iv, f. 3.— Adams, 

 Shells of Vermont, 154 (1842).— DeKay, N. Y. Moll. 73, pi. v, f. 78 

 (1843).— KusTER in Ch. ed. 2, 47, pi. viii, f. 22-26 (Linmasus).— 

 Gould, Inv. of Mass. 219, f. 150 (1841).— Haldeman, Mon. p. 31, 

 pi. X ; p. 48, pi. xiii, f. 16-18 (1842).— Akony. Can. Nat. II, 198, 

 fig. (1857). 



Limnxa acuta, Lea, Tr. Am. Phil. Soc. V, 114, pi. xix, f. 81 (1837) ; 

 Obs. I, 226. 



Limnaea obrussa, Say, J. A. N. Sc. V, 123 (1825) ; Bixney's ed. 113.— 

 DeKay, N. Y. Moll. 75 (1843). 



Limnsea phlludelphica, Lea, Proc. Am. Phil. Soc. II, 32 (1841) ; Tr. IX, 

 8 (1844); Obs. IV, 8. 



Limnaea fusiformis, Lea, Pr. Am. Phil. Soc. II, 33 (1841) ; Tr. IX, 10 

 (1844) ; Obs. IV, 10. 



From New England to Kansas. 



An authentic specimen of L. desidiosa, in the Academy's col- 

 lection, is drawn somewhat larger than nature in Fig. 68. 



Mr. Haldeman places L. obrunsa in the synonymy of L. desi- 

 diosa. Say's description here follows, and a drawing of an 

 authentic specimen from the Academy at Philadelphia. 



Limnaea obrussa. — Shell oblong, rather slender, pale yellowish testaceous ; 

 whirls five, slightly rounded ; apex acute ; suture deeply im- 

 pressed ; aperture not dilated, within pure white ; columella, pj^. 69. 

 with the sinus of the fold very obvious {Lister, pi. 114, f. 8 ?). 

 Total length nine-twentieths of an inch ; aperture one-fourth ; 

 breadth nearly one-fifth. 



All the individuals that have occurred were covered with an 

 earthy slime. They inhabit a small rivulet below the fish- 

 ponds at Harrowgate, the seat of my friend Mr. J. Gilliams. 

 (Say.) 



The descriptions of L. philadelphica, fusiformis, and acuta 

 here follow, as well as figures of them drawn from Mr. Lea's 

 original specimens, excepting L. acuta, which is copied from his 

 original figure. Haldeman and DeKay both place L. acuta in 

 the synonymy of L. desidiosa. Specimens labelled L. p)hiladel- 

 phica, by Mr. Lea, are in the Smithsonian collection from the 

 Yellowstone River. Kiister, I. c, places obrussa, acuta, and 

 philadeljyhica in the synonymy. 



Haldeman refers doubtfully L. casta to this species. It appears 

 to me, however, rather a synonym of L. columella. 



The name L. fusiformis is preoccupied by Sowerby (Min. 

 Conch. II, 155, pi. clxix, 1818). 



