TORNATELLID^. 355 



Operculum, when present, horny, ovate, narrow, composed of 

 few whorls. 



Shell spiral, ovate, convolute or involute, spire more or less 

 elevated, surface mostly spirall}^ punctated, aperture usually 

 high and narrow, truncate or roundish in front, columella solid. 



The genera and species referred to this famil}^ are mostly 

 fossil. The arrangement here followed is that of Dr. Stoliczka 

 {Pal. Indica^ ii, 398), being a modification of the classification 

 of Dr. F. B. Meek {Am. Jour. Sci., xxxv, 89, 1863). 



Subfamily TORNATELLIN^. 



Shell ovate, aperture anteriorly rounded, sonaetimes broadly 

 effuse, outer lip sharpened at the margin, columellar lip twisted 

 and often plicated in front. The recent species operculated. 



AcT^ONiNA, d'Orb. 



Syn.- -Trochactgeonina, Meek. Orthostoma, Desh. 



Distr. — 30 sp. Carboniferous to Eocene. A. Loi-ieriana, d'Orb. 

 (Ixxxviii, 46). 



Shell oval, elongated, conical or fusiform, with revolving punc- 

 tated stride ; aperture long and narrow, widened in front, entire ; 

 lip sharp ; columella thickened, but without plications. 



EucoNACT^ON, Meek, 1863. (Conactseon, Meek, 1863.) Shell 

 thin, obconic, gradually tapering anteriorly, spire either immersed 

 or elevated, aperture ver}'' long, equally narrow all through, ante- 

 riorly rounded, columella slightly thickened, smooth. Distr. — 

 Jurassic. A. concava, d'Orb. (Ixxxviii, 47 ). 



CYLiNDRiTES, Morr. and Lye. (Gonioc^dindrites, Meek.) Shell 

 subcylindrical or ovate, smooth, spire sunken or moderately 

 elevated, aperture narrow, very high, anteriorly rounded, sub- 

 effuse, columella twisted anteriorly into a distinctly conspicuous 

 fold. Distr.— Triassic and Jurassic. A. cuspidatus, Morris 

 (Ixxxviii, 48). 



CYLiNDROBULLiNA, von Ammon, 1818. Shell small, with ele- 

 vated, scalariform spire ; columella with a slight fold. Triassic to 

 Liassic. A. fragilis, Dunker. 



TORNATINA, A. Ad. 



Distr. — 24 sp. West Indies, United States, Mediterranean, 

 Philippines, China, Australia. On sandy bottoms, ranging to 

 35 fathoms. — Adams. Fossil, 13 sp. Tertiar3\ T. coarctata, 

 A. Ad. (Ixxxvii, 25). 



Shell cylindrical or fusiform, spire conspicuous, apex sinistral, 

 suture channeled, columella callous, 1 -plaited. 



Animal with a broad, trigonal head, rounded in front ; tentac- 

 ular lobes triangular, with eyes at their outer bases ; foot short, 

 truncated in front. 



