908 BULLETIN 92, UNITED STATES NATIONAL MUSEUM. 



Orthoceras Ignotum Foerste. 



Orthoceraa (Eu-orthoceras) ignotum Foerste, Proc. Boston Soc. Nat. Hist., 24, 



1889, p. 279, pi. 7, fig. 4; Geol. Surv. Ohio, 7, 1893, p. 539, pi. 32, fig. 4; pi. 36, 



figs. 6a-c; figs. 5-7, p. 540. 

 Orthoceras ignotum Foerste, Amer. Geol., 12, 1893, p. 236, figs. 5-7; Geol. Surv. 



Ohio, Pal., 7, 1893, p. 541, figs. 5-7 on p. 540. 

 Upper Medinan (Brassfield): Hanover, Indiana; near Dayton, Ohio. 



Orthoceras imbricatum (Wahlenberg). 



Orthoceratites imbricatus Wahlenburg, Nova Acta Upsal., 1827, p. 89. 

 Orthoceras imbricatum Sowerby in Murchison's Sil. Syst., 1839, p. 620, pi. 9, 



fig. 2.— Hall, Pal. New York, 2, 1852, p. 291, pi. 61, figs. 4a-c; pi. 62, figs. 



1-3.— Rogers, Geol. Pennsylvania, 2, pt. 2, 1858, p. 823, fig. 636.— Etheridge, 



Quart. Jour. Geol. Soc. London, 34, 1878, p. 607. 

 Silurian: Europe; Lockport and Rochester, New York; Cape Louis Napoleon, 



Arctic America. 



Orthoceras inceptum Foerste. See Cycloceras inceptum. 



Orthoceras inceptum var. acceleratum Foerste. See Cycloceras inceptum 

 acceleratum. 



Orthoceras indagator Billings. 



Orthoceras indagator Billings, Pal. Foss., 1, Geol. Surv. Canada, 1865, p. 349. 

 Canadian (Romaine): Mingan Islands, Quebec. 



Orthoceras infelix Billings. See Actinoceras infelix. 



Orthoceras insulare Barrande. See Endoceras insulare. 



Orthoceras irregtjlare McChesney. See Kionoceras cancellatum. 



Orthoceras Jamesi Hall and Whitfield. See Spyroceras jamesi. 



Orthoceras jolietense Meek and Worthen. 



Orthoceras jolietense Meek and Worthen, Proc. Acad. Nat. Sci. Philadelphia, 

 1865, p. 256; Geol. Surv. Illinois, 6, 1875, p. 465, pi. 26, fig. 5.— Keyes, Mis- 

 souri Geol. Surv., 5, 1894, p. 227. 



Niagaran (Racine): Joliet, Illinois. 



Orthoceras junceum Hall. 



Orthoceras junceum Hall, Pal. New York, 1, 1847, p. 204, pi. 47, figs. 3a-f.— 

 Chamberlin, Geol. Wisconsin, 1, 1883, p. 158, fig. — J. F. James, Jour. Cincin- 

 nati Soc. Nat. Hist., 8, 1886, p. 238.— Foord, Cat. Foss. Ceph. British Mus., 

 1, 1888, p. 10.— Clarke, Geol. Minnesota, 3, pt. 2, 1897, p. 790.— Cumings, 32d 

 Ann. Rep. Dep. Geol. Nat. Res. Indiana, 1908, p. 1037, pi. 51, figs. 5, 5c. — 

 Grabau and Shimer, N. A. Index Fossils, 2, 1910, p. 48, fig. 1246. 



Trenton: Watertown, New York. 



Black River: Minneapolis and Fountain, Minnesota (Decorah); Janesville, Wis- 

 consin (Platte ville). 



Orthoceras (Kionoceras) kentlandensis Kindle and Breger. See Kionoceras 

 kentlandense. 



Orthoceras l«ve Hall. See Orthoceras sublseve. 



Orthoceras Lamarcki Billings. See Protocycloceras lamarcki. 



