1124 BULLETIN 92, UNITED STATES NATIONAL MUSEUM. 



Rhynchotrema deckerense — Continued. 



Holderbergian: Two miles south of Tristates, New York (Decker Ferry); Cash 

 Valley, Devils Backbone, and Corriganville, Maryland; Keyser, West Vir- 

 ginia; Hyndman, Pennsylvania (Keyser). 



Rhynchotrema deckerense arcticum (Holtedahl). 



Stenochisma deckerensis var. arctica Holtedahl, Second Arct. Exp. "Fram", 



1898-1902, No. 32, 1914, p. 21, pi. 7, figs. 7, 8. 

 Helderbergian (lower beds): Southwestern Ellesmereland, Arctic America. 



Rhynchotrema dentatum (Hall). 



Atrypa dentata Hall, Pal. New York, 1, 1847, p. 148, pi. 33, fig. 14.— Emmons, 

 Amer. Geology, 1, pt. 2, 1855, p. 193, pi. 10, fig. 14. 



Rhynchonella dentata Hall, 12th Rep. New York State Cab. Nat. Hist., 1859, 

 p. 65.— Meek, Pal. Ohio, 1, 1873, p. 121, pi. 11, fig. 3.— Miller, Cincinnati 

 Quart. Jour. Sci., 2, 1875, p. 18. — White, 2d Ann. Rep. Indiana Bur. State 

 Geol., 1880, p. 490, pi. 1, figs. 12-14; 10th Rep. State Geol. Indiana, 1881, p. 

 122, pi. 1, figs. 12-14.— ?Keyes, Geol. Surv. Missouri, 5, 1895, p. 100, pi. 41, 

 fig. 3.— Lesley, Geol. Surv. Pennsylvania, Rep. P 4, 1889, p. 887, figs. 



Rhynchotrema dentata Hall and Clarke, Pal. New York, 8, pt. 2, 1893, p. 185 — 

 Weller, Geol. Surv. New Jersey Pal., 3, 1903, p. 159, pi. 10, figs. 19-22.— 

 Grabau and Shimer, N. A. Index Fossils, 1, 1907, p. 281, fig. 343e-g — 

 Cumings, 32d Ann. Rep. Dep. Geol. Nat. Res. Indiana, 1908, p. 932, pi. 36, 

 figs. 7-7d — Foerste, Bull. Sci. Lab. Denison Univ., 16, 1910, p. 29, pi. 2, fig. 

 16; pi. 3,fig. 12. 



Trenton: Turin, New York; New Jersey. 



Richmond: Dayton, Oxford, etc., Ohio; Indiana; Kentucky; Tennessee. 



Rhynchotrema dentatum arnheimense Foerste. 



Rhynchotrema dentata-arnheimensis Foerste, Bull. Sci. Lab. Denison Univ., 14, 



1909, p. 227, pi. 4, fig. 12; 16, 1910, p. 27, pi. 3, fig. 13; Ohio Nat., 12, 1912, 



p. 453, pi. 22, fig. 9. 

 Richmond (Arnheim): Anderson ville, etc., Ohio; Kentucky; Newsom, Clifton, 



etc., Tennessee. 



Rhynchotrema formosum (Hall). 



Rhynchonella formosa Hall, 10th Ann. Rep. New York State Cab. Nat. Hist., 



1859, p. 76, figs. 1-5; Pal. New York, 8, 1859, p. 236, pi. 35, figs. 6a-y. 

 Rhynchotrema formosum Schuchert, Bull. U. S. Geol. Surv., 87, 1897, p. 369. 

 Stenochisma formosa Maynard, Maryland Geol. Surv., Low. Dev., 1913, p. 349, 



pi. 62, figs. 25-29. 

 Helderbergian (Keyser): Devils Backbone, Cumberland, Cash Valley, Pinto, 



etc., Maryland; Hydman, Pennsylvania. 



Rhynchotrema? illinoisense Savage. 



Rynchotrema? illinoisensis Savage, Bull. Geol. Surv. Illinois, 23, 1913, p. 49, pi. 1, 



figs. 22, 23. 

 Upper Medinan (Girardeau): Near Thebes, Illinois. 



Rhynchotrema ina?quivalve (Castelnau). 



Spirifer imequivalvis Castelnau, Essai Syst. Sil. Amer. Sept., 1843, p. 40, pi. 14, 



fig.8. 

 Magnesian limestone: Drummond Island, Lake Huron. 



Observation. — Although the abundant Mohawkian species R. increbescens Hall 

 is commonly quoted under the above name, there is no certainty that the two 

 species are identical. Furthermore, the matter can not be settled without an 

 examination of Castelnau's types, and until this is done R. increbescens is recog- 

 nized as valid. 



