TRY. TUR.] 



GASTEROPODA. 



429 



nana, Foerste, 1885, Bull. Sci. Lab. Denison 



Univ., p. 94. Not properly defined. 

 pauper, Hall, syn. for P. halii. 

 pauper var. ohioense, Hall & Whitfield, 

 1875, Ohio Pal., vol. 2, p. 144, Niagara Gr. 

 rectilatera, Hall & Whitfield, 1872, 24th 

 Rep. N. Y. Mus. Nat. Hist., p. 193, Up. 

 Held. Gr. 

 tricarinatura, Billings, 1859, Can. Nat. & 



Geo ., vol. 4, p. 356, Calciferous Gr. 

 tricam'nnfa, Fee Trochonema meekannm. 

 umbilicatum, Hall, 

 1847, (Pleuroto- 

 inaria umbilica- 

 ta,)Pal.N.Y.,vol. 

 1, p. 43. Chazy to 

 Hud. Riv. Gr. 

 yandellanum, Hall 

 & Whitfield, 1872, 

 24th Rep. N. Y. 

 Mus. Nat. Hist., 

 ). 194, Up. Held. 



B,' 



FIG. 719. Trochonema 



umbilicatum. Trochus, Adanson, 



1757, Voy. Sene- 

 gal. [Ety. trochus, a hoop.] Not a 

 Palaeozoic genus. 



huronensis, Castelnau, 1843, Syst. Sil., p. 

 35. Not recognized. 



missouriensis, see Pleurotomaria missouri- 



ensis. 



TRYBLIDIUM, Lindstrom, 1880, Fragmenta 

 Silurica, p. 15. [Ety. trublion, a cup.] 

 Patelliform, obovate, acuminate ante- 

 riorly, enlarged posteriorly; muscular 

 scars in six disconnected pairs arranged 

 in an oblong circle open toward the 

 front. Type T. reticulatum. 



acutum, Whitfield, 1889, Bull. Am. Mus. 

 Nat. Hist., vol. 2, p. 45, Calciferous Gr. 



canadense, Whiteaves, 1884, Pal. Foss., 

 vol. 3, p. 31, Guelph Gr. 



conicum, Whitfield, 1886, Bull. Am. Mus. 

 Nat. Hist., vol. 1, p. 306, Birdseye Gr. 



erato, Billings, 1862, (Metoptoma erato,) 

 Pal. Foss., vol. 1, p. 39, Black Riv. Gr. 



eubule, Billings, 1862, (Metoptoma eu- 

 bule,) Pal. Foss., vol. 1, p. 38, Calcifer- 

 ous and Black Riv. Gr. 



FIG. 720.-Tryblidium nycteis. 



hyrie, Billings, 1862, (Metoptoma hyrie,) 

 Pal. Foss., vol. 1, p. 87, Quebec Gr. 



niobe, Billings, 1862, (Metoptoma niobe,) 

 Pal. Foss., vol. 1, p. 37, Calciferous Gr. 



nycteis, Billings, 1862, (Metoptoma nycteis, 

 Pal. Foes., vol.1, p. 38, Calciferous Gr. 



ovale, Whitfield, 1886, Bull. Am. Mus. 



Nat. Hist., vol. 1, p. 305, Birdseye Gr v 

 ovatum, Whitfield, 1886, Bull. Am. Mus. 

 Nat. Hist., vol. 1, p. 305, Birdseye Gr. 

 pileolum, Whitfield, 1889, Bull. Am. Mus. 

 Nat. Hist., vol. 2, p. 46, Calciferous Gr. 

 simplex, Billings, 1865, (Metoptoma sim- 

 plex,) Pal. Foss., vol. 1, p. 346, Calcifer- 

 ous Gr. 



TURBO, Klein, 1753, Tent. Meth. Ostr. [Ety. 

 turbo, top.] Shell thick, ovate ; body 

 whorl rounded, ventricose; spire small, 

 of several convex whorls, pointed ; sur- 

 face spirally grooved or nodulated ; 

 aperture large, nearly circular, slightly 

 produced and 

 broadly 

 rounded in 

 front, more 

 or less mod- 

 ified by the 

 preceding 

 whorl ; outer 

 and inner 

 lips thin ; op- 

 e r c u 1 u m 

 thick, shelly, 

 rugged with- 



FIG. 721.-Turbo marmo- out ;> flattened 



ratus. and spirally 



s u 1 c a t e d 



within. Type T. marmoratus. Not an 

 American Palaeozoic genus. The spe- 

 cies left here is, for want of material, 

 to refer them where they belong. 

 Ucarinatus, Troost, 1840. Not defined. 

 dilucula, see Holopea dilucula. 

 guadalupensis, Shumard, 1859, Trans St. 

 Louis Acad. Sci., vol. 1, p. 398, Per- 

 mian Gr. 



huronensis, Castelnau, 1843. Not recog- 

 nized. 



lineatus, see Pleurotomaria lineata. 

 obesus, Shumard, 1858, Trans. St. Louis 

 Acad. Sci., vol. 1, p. 202, Up. Coal 

 Meas. 

 (?) obscura, see Holopea 



obscura. 

 shumardi, see P'atys- 



toma shumardi. 

 tabulata, see Pleuroto- 

 maria tabulata. 

 tennesseensis, see Cyclo- 



nema tennesseense. 

 t e x a n u s, Shumard, 

 1859, Trans. St. Louis 

 Acad. Sci., vol. 1, p. 

 400, Coal Meas. 

 Turbonilla, Leach, 1826, 

 Risso Eur. Merio. 

 4. [Ety.di minutive 

 of Turbo, a genus.] 

 Not a Palsezoic 

 genus. FIG. 722. Tnrritella 



swallovana, see Aclis- imbricata. 



ina swallovana. 



TuRRtTELLA, Lamarck, 1801, Syst. An. sans 

 Vert., p. 89. Not a Palaeozoic genus. 

 Type T. imbricata. 



