DENDROID GRAPTOLITES OF HAMILTON, ONTARIO. 17 



The following notes are by Doctor Giirley : 



The description of 1SS4 adds that there are usually three or four branches 

 originating from near the same place on the short stipe, giving a lobed appear- 

 ance to the frond. The branches are rather more than 1 cm. long. The cells 

 occur on the lower sides of the branchlets (or pinnules). In 1 mm. there are 2 

 cells and 2 intercellular spaces. The slender branchlets are about 0.33 mm. 

 thick, and the whole frond is never more than 2 cm. wide. 



One specimen occurs, so labeled, in the Spencer collection, from the Niagara 

 dolomite, Hamilton, Ontario. After close study of it, I have concluded that it 

 is too obscure to add much to existing data, which amply suffice for the recog- 

 nition of the species in Hamilton collections. I find the branches about 0.25 to 

 0.3 mm. wide, and the theca> 50 to 55 in 25 mm. Whether or not the generic 

 reference is correct, it is the most natural provisional one, and may stand, pend- 

 ing better material. 



Genus DICTYONEMA Hall. 



Dictyoncma Hall, Amer. Journ. Sci. (2), XI, 1S51, p. 401; Nat. Hist. New 

 York, Pal., II, 1852, p. 174.— Pictet, Traite de Pal., 2d ed., IV, 1857, 

 p. 171.— Hall, Geol. Surv. Canada, Rep. Progr. for 1857, 1858, p. 142; 

 Canadian Nat. Geol., Ill, 1S5S, p. 174; Nat. Hist. New York, Pal.. Ill, 

 1859 [1861], p. 15; Geol. Surv. Canada, Decade 2, 1865, p. 136.— Salter, 

 Mem. Geol. Surv. Great Britain, III, 1866, p. 331 (2d ed., 1881, p. 

 535).— Hall, 20th Rep. New York State Cab. Hist., 1868, p. 218 (rev. 

 ed., 1868 [1870], p. 252).— Nicholson, Mon. Brit. Graptolitidc-e, 1872, 

 p. 129.— Dames, Zeits. d. d. geol. Gesell., XXV, 1873, p. 383.— Zittel, 

 Handbuch d. Pal., I, 1879, p. 289.— Spencer, Trans. Acad. Sci. St. Louis, 

 IV, 1884, pp. 502, 572 ; Bull. Mus. Univ. State Missouri, I, 1884, p. 22.— 

 Miller, North Amer. Geol. and Pal., 1889, p. 185. — Holm. Bihaug till 

 K. Sv. Vet.-Akad. Handl., XVI, Afd. IV, No. 7, 1890, p. 4.— Moberg, 

 Geol. Foren. Stockholm Forhandl., XIII, 1891, p. 210.— Matthew, 

 Trans. Royal Soc. Canada, IX, sect. IV, 1892, \). 33.— James, Journ. 

 Cincinnati Soc. Nat, Hist, XIV, Pt. 2, 1892, p. 1.53.— Moberg, Geol. 

 Foren. Stockholm Forhandl., XVI, 1894, p. 236. — Tornquist. Geol. 

 Foren. Stockholm Forhandl., XVI, 1894, p. 380.— Pocta, Syst. Sil. 

 Centre Boheme, VIII, Pt. 1, 1894, p. 190.— Pritchard, Proc. Royal Soc. 

 Victoria, new ser., VII, 1895, p. 27. — Wiman, Natural Science, IX, 



1896, p. 243.— KoKEN, Die Leitfossilien, 1896, p. 327.— Gurley, Journ. 

 Geol., IV, 1896. p. 81— Frech, Leth. geog., I Th., Leth. Pal., I, 3 Lief.. 



1897, p. 557. — Roemer and Frech, Leth. geog., I Th., Leth. Pal., I, 3 

 Lief., 1897, p. 569.— Walther, Zeits. d. d. geol. Gesell., XLIX, 1897, 

 pp. 250, 253.— Grabau, Bull. Buffalo Soc. Nat. Sci., VI, 1899, p. 119; 

 Bull. Buffalo Soc. Nat. Sci., VII, 1901, p. 133; Bull. New York State 

 Mus., IX, 1901, p. 133. — Ruedemann, New York State Mus., Mem. 7, 

 1904, \\ 591. 



Dictyogrupiuft Hopkinson and Lapwortii, Quart. Journ. Geol. Soc. Lon- 

 don. XXXI, 1875, p. 667.— Moberg, Geol. Foren. Stockholm Forhandl., 

 XVI, 1894, p. 236.— Tornquist, Geol. Foren. Stockholm Forhandl., XVI, 

 1894, p. 380. 



A very complete history of this genus (consisting of about forty 

 pages of typewritten manuscript) was compiled by Doctor Gurley, 



