604 BULLETIN Q2, UNITED STATES NATIONAL MUSEUM. 



Helopora dlrarlcata — Continued. 



Clack Paver (Decorah): Minneapolis, etc., Minnesota. 

 Middle Ordovician (Kuckers): Esthonia, Russia. 

 Cotypes.— Cat. No. 43568, U.S.N.M. 



Helopora elegans Ulrich. 



Ilelopora elegans Ulrich, Geol. Minnesota, 3, 1893, p. 194, fig. 11. — Cumings, 32d 



Ann. Rep. Dep. Geol. Nat. Res. Indiana, 1908, p. 837, pi. 29, fig. 9. 

 Richxaond (Whitewater): Elanchester, Oxford, etc., Ohio; Richmond and Vcr- 



eailles, Indiana. 

 Uolotype.—C&t. No. 43566, U.S.N.M. 



Helopora formosa Billings. 



Ilelopora formosa Billings, Catal. Sil. Foss. Anticosti, 1866, p. 37. 

 Helopora nodosa Billings, Catal. Sil. Foss. Anticosti, 1866, p. 33. 

 Nematopora formosa Ulrich, Geol. Surv. Illinois, 8, 1890, p. 645. 

 Gamachian (EUis Bay) and Anticostian (Becsie River-Jupiter River): East 

 Point, East Jupiter River, East River, etc., Anticosti. 



Helopora fragills Hall. 



Helopora fragilis Hall, Pal. New York, 2, 1852, p. 44, pi. 18, figs. 3a-f.— Nicholson 

 and Hinde, Canadian Jour., n. s., 14, 1874, p. 141. — Nicholson, Pal. Province 

 Ontario, 1875, p. 44, fig. 19, figs. 3, 3a.— Ulrich, American Geol., 1, 1888, 

 p. 233, fig. 2a-e.— Miller, N. A. Geol. Pal., figs. 485a-e, 486 (p. 308).— Ulrich, 

 Geol. Surv. Illinois, 8, p. 642, figs. 18a-e (p. 643), pi. 29, fig. 5a.— Grabau, 

 Bull. New York State Mus., 45, 1901, p. 173, fig. 74; Bull. Buffalo Soc. Nat. 

 Sci., 7, 1901, p. 173, fig. 74.— Grabau and Shimer, N. A. Index Fossils, 1, 

 1907, p. 152, fig. 207. 



Upper Medinan (Cataract): Western New York; Flamborough Head, etc., 

 Ontario. 



Lower Clinton: Wayne County, etc.. New York. 



Plesiotype.—C&t. No. 43369, U.S.N.M. 



Helopora fragilis acadiensis Hall. Not defined. 



Helopora fragilis var. acadiensis Hall, Canadian Nat. Geol., 5, 1860, p. 159. 

 Silurian: Nova Scotia. 



Helopora harrlsl James. 



Ilelopora harrisi James, Paleontologist, No. 7, 1883, p. 58, pi. 2, figs. 2-2b. — 

 Ulrich, Contr. Micro-Pal. Cambro-Sil., pt. 2, 1889, p. 45; Geol. Minnesota, 3, 

 1893, p. 195, pi. 3, figs, lib, c, 12.— Whiteaves, Pal. Foss., 3, pt. 2, 1895, 

 p. 117.— Simpson, 14th Ann. Rep. State Geol. New York for 1894, 1897, figs. 

 113-115 (p. 548).— Bassler, Proc. U. S. Nat. Mus., 30, 1906, p. 40, pi. 7, fig. 8.— 

 Cumings, 32d Ann. Rep. Dep. Geol. Nat. Res. Indiana, 1908, p. 837, pi. 29, 

 figs. 10-lOb.— Bassler, Zittel-Eastman Textb. Pal.. 1913, p. 343, fig. 501f. 



Richmond: Waynesville, ^tc.. Oliio; Indiana (Wayneaville, Liberty); ?Stony 

 Mountain, Manitoba. 



Plesiotij pes. —Cat. No. 43569, U.S.N.M. 



Helopora Imbrlcata Ulrich. 



Ilelopora irabricata Ulrich, Geol. Sur\'. Illinois, 8, 1890, p. 644, pi. 29, fig. 5. 

 Richmond: Wilmington, Illinois (Fernvale); Charleton Point, etc., Anticoeti 

 (Charleton). 

 Observ'ation.— This form rruiy bo the tertiary eegmenta of Arthroclema angulare 

 ririch. 



Helopora irheoularis Billings. Seo Trematopora irregularis. 



