42 LAND AND FRESII-AVATER SHELLS OF N. A. PART III. 



Paludina cornea, Valenciennes? Rec. d'Obs. II, 255, 1833. 



Paludina inteijra, Sav, 1821, Binney's ed. p. 69 ; Journ. A. N. Sc. II, 174 

 (1821).— Haldeman, Mon. p. 10, pi. iii (1840).— Adams, in Thomp. 

 Vermont, p. 152 (1842).— DeKay, N. Y. Moll. p. 84, pi. vii, f. 132 

 (1843).— KusTER, Chemn. ed. 2, p. 17, tab. iii, f. 11-13.— Cheku, 

 111. Conch, pi. i, f. 9-13.— Philippi, Conch. Ill, 4, pi. i, f. 7 (1848). 



Paludina genicula, Conkad, N. Fr. W. Shells, p. 48, pi. viii, fig. 3, 1834 ; 

 ed. Chenu, 23, pi. iv, f. 20. — Kiistek in Chemn. ed. 2, p. 14, pi. iii, 

 fig. 5, 6 (1852).— MiiLLEE, Syn. Test, in 1834 prom. p. 39.— Halde- 

 man, Mon. p. 15, pi. V (1840).— DeKay, N. Y. Moll. p. bG (1843).— 

 Chend, Illust. Conch, pi. i, f. 18-19. 



Paludina heros, DeKay, olim, N. Y. Prel. Rep. 1839, p. 32 ; Moll. p. 85 

 (1843). 



Paludina subsolida, Anthony, Proc. Ac. N. Sc. Phila. 1860, p. 71. — Tkyon, 

 Phil. Pr. 18«2, 452. 



Paludina decapitata, Anthony, Proc. A. N. S. Phila. 1860, p. 71. — Reeve, 

 Con. Icon, pi. xi, f. 75 (1863). 



Paludina milesii, Lea, Proc. Phila. Acad. Nat. Sc. 186?, 156. 



Helix dissimilis, Wood, Ind. Suppl. pi. vii, f. 18 (1828) ; Hanley's ed. 

 p. 226 (1856). 



Helix decisa, Eaton, Zool. Text-Book, 196 (1826). 



Lymnula ventricosa, Rafinesq0e, MSS. 



Ambloxis (^Amblosfoma) major, Rafinesque, MSS. 



Cochlea Viryiniana, ^c. Lister, Conch, t. cxxvii, f. 27 (1770). 



Petivek, Gazophyl. t. cxvi, f. 18. 



Found in all eastern iS'ortli America, from the Rio Grande to 

 Nova Scotia and the Canadas. 



The first point to be decided in considering this species is what 

 shell Mr. Say had before him in drawing up the description of 

 Jjimnaea decisa, which name was subsequently changed to Palu- 

 dina decisa. It is from the original description and figure alone 

 that this point can be decided. They are both copied below, as 

 given in the American edition of Nicholson's Encyclopedia. 



Limnxa decisa, Say. — Shell subconic, olivaceous, truncated at the 

 apex ; whirls four, wrinkled across and banded with 

 Pig. 83. minute distant striae; terminal whirl very short; suture 



impressed and conspicuous ; aperture subovate, more 

 than half of the length of the sliell, entire ; within blu- 

 ish-white. Operculum coriaceous, elevated on the disk 

 and concentrically striated. Length one inch, breadth 

 three-fourths. 



Cochlea vii-gininna ^ flava viridescens, nan fasciata. 

 Lister, Conch, tab. cxxvii, fig. 27. 



tdmncm decisa. The young shell resembles P. subcarinata, but the whirls _ 



