410 BULLETIN 92, UNITED STATES NATIONAL MUSEUM. 



Dlcellograptus divaricatus — Continued. 



Didymograptus divaricatus Nicholson, Ann. Mag. Nat. Hist., 5, 1868, p. 351, pi. 

 7, fig. 4; Men. British Grapt., 1872, p. 55, text fig. 30. 



Dicellograptus divaricatus Hopkinson, Geol. Mag., 8, 1871, p. 25, pi. 1, fig. 4. — 

 Hopkinsonand Lapworth, Quart. Jour. Geol. Soc, 31, 1875, p. 654, pi. 34, figs. 

 3a, b. — Lapworth, Roy. Soc. Can. Proc. and Trans., 5, sec. 4, 1886, p. 184. — 

 Walcott, Geol. Soc. Am. Bull., 1, 1890, p. 339.— T. S. Hall, Rec. Geol. Surv. 

 N. S. Wales, 7, pt. 2, 1902, p. 3, pi. 12, fig. 3; pi. 13, fig. 3.— Elles and Wood, 

 Mon. British Grapt., pt. 4, 1904, p. 143, pi. 20, figs. 5a, 5b. — Grabau and Shlmer, 

 N. A. Index Fossils, 1, 1906, p. 32, fig. 53c. — Ruedemann, Mem. New York 

 State Mus., 11, pt. 2, 1908, pp. 296-299, pi. 18, figs. 4, 212-214. 



Dicellograptus moffatensis var. divaricatus Lapworth, Belfast Nat. Field Club, 

 Rep. and Proc, 1, pt. 4, 1877; app., p. 141, pi. 7, fig. 10.— Ami, Can. Geol. 

 Surv., Ann. Rep. 3, pt. 2, 1889, p. 60K, 116K. 



Dicranograptus divaricatus Walcott, Alb. Inst. Trans., 10, 1883, (adv. sheets, 

 1879, p. 34). 



Dicranograptus (Dicellograptus) divaricatus Roemer and Freeh, Leth. Pal., 1, 

 3 Lief, p. 618. 



Chazyan (Normanskill): Kenwood, Glenmont, Stockport, etc., New York; Ne- 

 vada; Canada; Arkansas. 



Middle Ordovician: Scotland and Wales (Glenkiln); New South Wales; Australia. 



Dicellograptus divaricatus bicurvatus Ruedemann. 



Dicellograptus elegans Gurley, Geol. Surv. Arkansas, Ann. Rep. for 1890, 3, 1892, 

 p. 414; Jour. Geol., 4, 1896, pp. 71, 95. 



Dicellograptus divaricatus var. bicurvatus Ruedemann, Mem. New York State 

 Mus., 11, pt. 2, 1908, p. 300, pi. 18, fig. 8, text fig. 216. 



Chazyan (Normanskill): Kenwood and Glenwood, New York; Ouachita Moun- 

 tains, Oklahoma (Talihina); Arkansas (Stringtown). 

 Obser\^ation. — The species listed by Gurley as D. elegans Cari'uthers in all 



probability refers to this variety. See Ruedemann, Mem. New York State Mus., 



11, pt. 2, 1908, p. 312. 



Dicellograptus divaricatus Lapworth (1876). See Dicellograptus divaricatus 

 rigidus. 



Dicellograptus divaricatus rectus Ruedemann. 



Dicellograptus divaricatus var. rectus Ruedemann, Bull. New York State Mus., 



11, pt. 2, 1908, p. 299, pi. 18, fig. 7, text fig. 215. 

 Chazyan (Normanskill): Kenwood and Speigletown, New York. 



Dicellograptus divaricatus rigidus Lapworth. 



Dicellograptus divaricatus Lapworth, Cat. West. Scott. Foss., 1876, pi. 4, fig. 86. 

 Dicellograptus moffatensis var. divaricatus Lapworth, Belfast Nat. Field Club, 



Rep. and Proc, 1, pt. 4, app. 1877, p. 141, pi. 7, fig. 10. 

 Dicellograptus rigidus Gurley, Geol. Surv. Arkansas, 3d Ann. Rep., 1890, p. 416; 



Jour. Geol., 4, 1896, p. 297. 

 Dicellograptus divaricatus var. rigidus Lapworth, Ann. Mag. Nat. Hist., 5th ser., 



5, 1880, p. 163, pi. 5, fig. 20.— Elles and Wood, Mon. British Grapt., 1904, 



p. 144, fig. 88a; pi. 20, figs. 6a-e. — Ruedemann, Mem. New York State Mus., 



11, pt. 2, 1908, p. 301. 

 Ordovician: Great Britain (Glenkiln); Arkansas and Oklahoma (Normanskill- 



Stringtown). 

 Plmotype.—C2it. No. 54259, U.S.N.M. 



