BIBLIOGRAPHIC LIST OP GENERA AND SPECIES. 407 



DIaphorostoma hemlsphericum (Hall). 



Euomphalus hemisphericus Hall, Nat. Hist. New York, Geol., 4, 1843, p. 109, 



figs. 1, 2; p. 110, tab. 16, figs. 1, 2. 



Straparollus hemisphericus D'Orbigny, Prodr. Pal., 1, 1849, p. 29 (gen. ref.) 

 Platyostoma hemispherica Hall, Pal. New York, 2, 1852, p. 288, pi. 60, fig. 2a, 



b. Lesley, Geol. Surv. Pennsylvania, Rep. P 4, 1889, p. 692, figs. 

 Clinton (Rochester): Rochester, Lockport, etc., New York. 



DIaphorostoma humile (Billings). 



Cyclonema humilis Billings, Cat. Sil. Foss. Anticosti, Geol. Surv. Canada, 1866, 



p. 56. 

 Gamachian (Ellis Bay) and Anticostian (Gun River-Chicotte) : The Jumpers, etc., 



Anticosti. 



Diaphorostoma illinoisense Savage. 



Diaphorostoma illinoisensis Savage, Bull. Geol. Surv., Illinois, 23, 1913, p. 118, 



pi. 7, fig. 19. 

 Upper Medinan (Channahon) : Will County, Illinois. 



Diaphorostoma ulagarense (Hall). 



Platyostoma niagarensis Hall, Pal. New York, 2, 1852, p. 287, pi. 60, figs, la-v. 

 Roemer, Sil. Fauna West. Tennessee, Breslau, 1860, p. 75, pi. 5, fig. 15. 

 Hall, Trans. Albany Inst., 4, 1863, p. 227 (loc. occ.); 20th Rep. New York 

 State Cab. Hist., 1868, p. 342, 393 (loc. occ.) (Extras, 1865), rev. ed., 1870, 

 pp. 390, 432; 28th Rep. New York State Mus. Nat. Hist., doc. ed., 1877, pi. 

 28, figs. 1-12; pi. 29, figs. 1-15; pi. 31, fig. 3; Mus. ed., 1879, p. 175, pi. 28, 

 figs. 1-12; pi. 29, figs. 1-15. White, 2d Ann. Rep. Indiana Dep. Stat. Geol., 

 1880, p. 497, pi. 3, figs. 7, 8. Zittel, Handb. Pal., 2, 1882, p. 217, fig. 297. 

 Hall, llth Ann. Rep. Indiana Dep. Geol. Nat. Hist., 1881, p. 318, pi. 29, 

 figs. 1-12; 13?, pi. 30, figs. 1-15. Foerste, Bull. Sci. Lab. Denison Univ., 1, 

 1885, p. 97, pi. 13, figs. 3a, b; fig. 22. Nettelroth, Kentucky Foss. Shells, 

 Geol. Surv. Kentucky, 1889, p. 185, pi. 33, fig. 30. Lesley, Geol. Surv. 

 Pennsylvania, Rep. P 4, 1889, p. 693, figs. Miller, N. A. Geol. Pal., 1889, 

 p. 418, fig. 697. Rowley in Greene, Cont. Indiana Pal., pt. 8, 1901, p. 67, 

 pi. 23, fig. 12. Maynard, Maryland Geol. Surv., Low. Dev., 1913, p. 483, pi. 

 57, figs. 3, 4. 



Platyostoma (Diaphorostoma) niagarense Grabau, Amer. Nat., 36, 1902, p. 939. 



Diaphorostoma niagarense Grabau, Bull. Buffalo Soc. Nat. Sci., 8, 1901, p. 212, 

 fig. 141; Bull. New York State Mus., 45, 1901, p. 212, fig. 141. Clarke and 

 Ruedemann, Mem. New York State Mus., 5, 1903, p. 59, pi. 10, figs. 14-16. 

 Grabau and Shimer, N. A. Index Fossils, 1, 1909, p. 679, fig. 951. Savage, 

 Bull. Geol. Surv. Illinois, 23, 1913, p. 102, pi. 6, fig. 1. 



Platyceras (Platystoma) niagarensis Foerste, Geol. Surv. Ohio, 7, 1893, p. 553, 

 pi. 25, figs. 3, 22. 



Platyceras (Diaphorostoma) cornutum Kindle and Breger, 28th Ann. Rep. Dep. 

 Geol. Nat. Res. Indiana, 1904, p. 453, pi. 13, figs. 9-16. 



Strophostylus niagarensis Keyes, Amer. Nat., 24, 1890, pi. 33, fig. 2; Proc. Iowa 

 Acad. Sci., 1, pt. 2, 1892, p. 25. 



Silurian: Lockport, Rochester, etc., New York. As at present identified a 

 widely distributed species in North America ranging from the Brassfield to 

 the Keyser formation of the Helderbergian. 



Plesiotype. Cat. No. 53232, U.S.N.M. (Nettelroth). 



Observation. D. niagarensis Hall has been identified with Platyceras cornutum 

 Hisinger, but until the two have been more closely compared it is preferred 

 to leave them distinct. 



