

BIBLIOGRAPHIC LIST OF GENERA AND SPECIES. 429 



HDYMOGRAPTUS- Continued. 



Didymograptus Hall, 20th Rep. New York State Cab. Nat. Hist., 1868, pp. 217, 234; 

 rev. ed. (1870), p. 251. Zittel, Handb. Pal., 1, 1879, p. 298. Tullberg, 

 Sveriges Geol. Unders., ser. C, No. 55, 1883, p. 12. Hermann, Geol. Mag^, 

 dec. 3, 3, 1886, p. 14. Miller, N. A. Geol. Pal., 1889, p. 185. Tornquist, 

 Lunds Univers. Arsskrift, 26, No. 4, 1890, p. 15. Barrois, Ann. Soc. Geol. 

 du Nord, 21, Lille, 1893, p. 108. Holm, Sveriges Geol. Unders., ser. C, No. 

 150, 1895, p. 15; Geol. Foren. Stockholm ForhandL, 17, 1895, p. 331; Geol. 

 Mag., dec. 4, 2, 1895, pp. 433, 439, pi. 14, figs. 1-3, 7, 8. Nicholson and Murie, 

 Geol. Mag., dec. 4, 2, 1895, pp. 530-535, figs. Koken, Die Leitfossilien, Leip- 

 zig, 1896, p. 328. Wiman, Bull. Geol. Inst. Univ. Upsala, 2, pt. 2, No. 4, 

 1896, p. 266; Nat. Sci., 9, 1896, p. 191. Walther, Zeits. d. d. geol. Gesell., 

 49, 1897, p. 251. Roemer and Freeh, Leth. geog., 1 Theil, Leth. Pal., 1, 

 3 Lief., 1897, p. 587. Ruedemann, Amer. Nat., 32, 1898, p. 5; Zittel-East- 

 man Textb. Pal., 1, 1900, p. 118. Tornquist, Lunds Univers. Arsskrift, 37, 

 No. 5, 1901, p. 10. Elles and Wood, Mon. British Grapt., Pal. Soc., 1901, 

 p. 5. Ruedemann, Mem. New York State Mus., 7, 1904, p. 666, 668. 

 Grabau and Shimer, N. A. Index Fossils, 1, 1906, p. 30. Ruedemann, Mem. 

 New York State Mus., 11, pt. 2, 1908, p. 247; Zittel-Eastman Textb. Pal., 

 2d ed., 1913, p. 129. 



idyinograptus acutidens Lapworth. 



Didymograptus affinis Hopkinsou, Quart. Jour. Geol. Soc., 31, 1875, pi. 33, 



figs. 6b, c. 

 Didymograptus acutidens (Lapworth MS.) Elles and Wood, Mon. British Grapt., 



pt. 1, Pal. Soc., 1901, p. 25, pi. 2, figs. 3a-d. Ruedemann, Mem. New York 



State Mus., 7, pt. 1, 1904, pp. 683, 684, pi. 13, fig. 15, text figs. 77, 78. 

 Canadian: St. Davids District, Wales, and South Shropshire, England (Arenig); 



Deepkill, Rensselaer County, New York (Deepkill, Didymograptus bifidus 



zone). 



DIDYMOGRAPTUS AFFINIS Hopkinson. See Didymograptus acutidens. 



Didymograptus arcuatus (Hall). 



Graptolithus arcuatus Hall, Geol. Surv. Canada, dec. 2, 1865, p. 79, pi. 2, figs. 



6-10. 

 Graptolithus (Monoprion) arcuatus Hall, 20th Rep. New York State Cab. Nat. 



Hist., 1868, p. 226; rev. ed. (1870), p. 260; p. 223. 

 Didymograpsus arcuatus Gurley, Jour. Geol., 4, 1896, p. 96 (gen. ref.). 

 Didymograptus arcuatus Elles and Wood, Mon. British Grapt., Pal. Soc., 1903, 



p. li (gen. ref.). 

 Canadian (Levis, Didymograptus zone): Point Le vis, Quebec. 



lymograptus bifidus (Hall). 

 Graptolithus bifidus Hall, Canadian Nat. and Geol., 3, 1858, p. 164; Geol. Surv. 



Canada, Rep. Progr. for 1857, 1858, p. 130; Geol. Surv. Canada, dec. 2, 1865, 



p. 73, pi. 1, figs. 16-18; pi. 3, figs. 9, 10. 

 Graptolithus (Monoprion) bifidus Hall, 20th Rep. New York State .Cab. Nat. Hist. 



1869, p. 226, pi. 3, figs. 13, 14; rev. ed., 1870, p. 241; p. 223. 

 Didymograptus bifidus Nicholson, Quart. Jour. Geol. Soc. London, 24, 1868, p. 



136; Ann. Mag. Nat. Hist., 4th eer., 5, p. 346, fig. 7. Hopkinson, Quart. 



Jour. Geol. Soc., 31, 1875, p. 646, pi. 33, figs. 8a-e. Brogger, Die sil. Etagen 2, 



3, etc. Kristiania, 1882, p. 41. Herrmann, Geol. Mag., 3d ser., 3, 1886, p. 15. 



Ami, Geol. Surv. Canada Rep., 2d ser., 3, pt. 2, 1889, p. 116k. Barrois, Ann. 



de la Soc. Geol. du Nord., 20, 1892, p. 92. Elles, Quart. Jour. Geol. Soc. 



London, 54, 1898, p. 511. Elles and Wood, Mon. British Grapt., pt. 1, Pal. 



