546 BULLETIN 92, UNITED STATES NATIONAL MUSEUM. 



Gazacrinus minor Weller. 



Gazacrinus minor Weller, Bull. CMcago Acad. Sci., Nat. Hist. Surv., 4, pt. 1, 



1900, p. 80, pi. 3, figs. 3, 4. 

 Niagaran (Racine): Bridgeport, Illinois. 



Gazacrinus ventricosus (Wachsmuth and Springer). 



Idiocrinus ventricosus Wachsmuth and Springer, Amer. Geol., 10, 1892, p. 137; 



Mem. Mus. Comp. Zool. Harvard, 20, 1897, p. 205, pi. 18, fig. 9a, b. 

 Gazacrinus ventricosus Bather, Treatise on Zool., pt. 3, Echinodenna, London, 



1900, p. 188, fig. 

 Niagaran (Laurel): St. Paul, Shelby County, Indiana. 



GEINITZELLA W T aagen and Wentzel. See Batostomella Ulrich. 



GEISONOCERAS Hyatt. Genotype: Orthoceras rivale Barrande. 



Geisonoceras Hyatt, Proc. Boston Soc. Nat. Hist., 22, 1884, p. 275; Zittel-Eastman 



Textb. Pal., 1, 1900, p. 518; ibid., 2d ed., 1913, p. 598. 



p. 437, 



Geisonoceras shumardi (Billings). 



Orthoceras shumardi Billings, Can. Nat. Geol., 4, 1859, p. 460, fig. 36. 

 Geisonoceras shumardi Ruedemann, Bull. New York State Mus., 90, 1906, p. 



pi. 12, fig. 4. 

 Orthoceras (Geisonoceras) shumardi Grabau and Shimer, N. A. Index Fossils, 2, 



1910, p. 48. 

 Chazyan: Mingan Islands, Canada (Mingan); Chazy, New York (Day Point, 



Crown Point). 



GEOCRINUS D'Orbigny. See Periechocrinus Austin. 



GERASAPHES Clarke. Genotype: G. ulrichana Clarke. 



Gerasaphes Clarke, Geol. Minnesota, 3, pt. 2, 1894, p. 710. 



Gerasaphes ulrichana Clarke. 



Gerasaphes ulrichana Clarke, Geol. Minnesota, 3, pt. 2, 1894, p. 710, figs. 14-16. 



Miller, N. A. Geol. Pal., 2d App., 1897, p. 788. Ruedemann, Bull. New 



York State Mus., 49, 1906, p. 60. 



Trenton (Upper): Mouth of Licking River, Covington, Kentucky. 

 Holotype Cat. No. 41951, U.S.N.M. 



GILBERTSOCRINITES AMERicANUs Troost. See Diabolocrinus vesperalis. 

 GILBERTSOCRINITES(?) DUBius Troost. See Periechocrinus dubius. 

 GILBERTSOCRINITES ROEMERI Troost. See Dimerocrinus roemeri. 



GIRVANELLA Nicholson and Etheridge. 



Genotype: G. problematica Nicholson and Etheridge. 



Girvanella Nicholson and Etheridge, Mon. Sil. Foss. Girvan Dist., 1878, p. 23, 

 pi. 9, fig. 24. Nicholson, Geol. Mag., dec. 3, 4, 1888, p. 22. James, J. F., 

 Jour. Cincinnati Soc. Nat. Hist., 14, pt. 1, 1891, pp. 50, 51. Dawson, Canadian 

 Rec. Sci., 7, 1896, p. 212. 



Strephochetus Seely, Amer. Jour. Sci. Arts, 3d ser., 30, 1885, p. 357; ibid., 32, 

 1886, p. 31. Walcott, Bull. U. S. Geol. Surv., 30, 1886, p. 91. Hinde, Geol. 

 Mag., dec. 3, 4, 1887, p. 227. Miller, N. A. Geol. Pal., 1889, p. 165. Seely, 

 Rep. State Geol. Vermont, 3, 1902, p. 156. (Genotype: S. ocellatus Seely.) 



Girvanella antiqua Dawson. 



Girvanella antiqua Dawson, Canadian Rec. Sci., 7, 1896, p. 214. 

 Cambrian or Lower Ordovician bowlder: Little Metis, Quebec. 



