182 TRUNCATELLA. 
Truncalella L. Pfeiffer 1841. Symb. ad hist. Helic. p. 4. 
— Reeve 1841. Proceed. Zool. Soc. IX. p. 76 et 1842. Conch. 
syst. Il. p. 93. 
EZ G. B. Somerby jun. 1842. Conch. Mah. ed. II. p. 280. 
— Thompson 1844. Report Faun. Irel. p. 255. 
— Philippi 1844. Enum. Moll. Sicil. II. p. 133. 
— Thorpe 1844. Brit. mar, Conchol. p. 146. 
— Catlom 1845. Conch. Nomencl p. 169. 
— L. Pfeiffer 1846 in Zeitschr. f. Malakoz. p. 177 et 1847. 
Ibid. p. 112. 
— Gray 1847 in Proc. Zool. Soc. XV. p. 159. 
— Herrmannsen 1849. Ind. gen. Malac. prim. II. p. 626. 
-— Jay 1850. Catal. Ed. IV. p. 252. 
— J. E. Gray 1850 in M. E. Gray Fig. Moll. Anim. IV. p. 85. 
-— C. B. 4dams 1851. Contrib. to Conch. Nr. 9. p. 132. 
Ann. Lyc. New-York V. p. 436. 
— Dupuy 1851. Moll. de France p. 531. *) 
— Woodward 1851. Man. Moll. I. p. 137. **) 
-— Forbes et Hanley 1853. Brit. Moll. IV. p. 316. 
c Philippi 1853. Handb. d. Conch. p. 263. 
— Lowe 1854-in Proc. Zool. Soc. XXII. p. 217. 
— Poey 1854 Memor. hist. nat. Cuba I. p. 393. 
— Küsler 1855. Die Gattungen Truncatella u. Paludinella. In 
Chemn. Conch. Cab. Ed. nov. Vol. I. 
— H. ct .4. Adams 1856. Gen. rec. Moll. II. p. 310. ***) 
Fidelis Risso 1826. Mist. Eur. mérid. IV. p. 121. 
Choristoma De Crist. et Jan 1832. Catal. Mantissa p. 3. 1) 
— Hartm. 1840. Erd- und Süssw. Gast. L. System. Uebers. 
*) Animal elongatum, spirale, capite elongato, proboscidiformi, in ro- 
strum bilobem producto, tentaculis brevioribus, ad latera capitis dispositis 
et divergentibus, punctulos oculares in latere superiore neque in exteriore 
gerentibus; disco brevi, elliptico, utrinque rotundato. — Testa turrita, cy- 
lindroidea, apice papillata, subtruncata vel truncata, epidermide destituta ; 
apertura ovata vel ovato-piriformi, peristomate continuo vel subcontinuo. — 
Operculum corneum, tenue et minime spirale. (Dupuy l. c.) 
**) Shell minute, cylindrieal, truncated;  whirls striated transversely; 
aperture oval, entire; peristome continuous. Operculum sub-spiral! — Ani- 
mal with short, diverging triangular tentacles; eyes centrally behind; head 
bi-lobed ; foot short, rounded at each end. (Woodw. l. c.) 
***) Opereulum sub-membranaceous, obsoletely spiral. Shell, in the 
young, subulately turreted, in the adult, cylindrical and truncated; aperture 
oblong-oval; peristome simple or double, margins rather wide apart, united 
by a callus. (H. et A. Adams 1, e.) 
1) Animale tentacula duo, brevia, apice subaceuminata. Oculi ad ten- 
taculorum basin posteriorem. Os longa proboscide instructum. Pes bre- 
vis. — Testa cylindrica, crassa, apice obtusa; apertura ovata marginibus 
lamina columellari interposita disjunctis. Operculum semiovatum, striatum, 
(Janl. c.) 
