550 E. J. Garwood and J. E. Marr — On Carbomferous Zones. 



extend their inquiries as far back as the Laurentian in the search 

 for Eozoic life. 



In this respect the study and discussion of Eozoon have not been 

 without use, in directing attention to the possibility of finding 

 organic remains in the older crystalline roclis, to the danger of 

 confounding them in their peculiar condition with merely mineral 

 structui'es, to the state of preservation of organic remains in the 

 older formations, and to the origin and significance of the large 

 deposits of limestone, dolomite, hydrous silicates, iron ore, graphite, 

 and apatite, laid up in certain horizons of the Eozoic rocks. 

 Questions of this kind have been greatly advanced toward their 

 satisfactory solution since the discovery of Eozoon in 185S, and in 

 some degree at least in consequence of the interest excited by that 

 discovery. It is hoped that the present notes may tend in the same 

 direction, and that, whether or not they succeed in removing any 

 existing scepticism in respect to Eozoon, they may help to stimulate 

 and guide the search for those beginnings of life, which there are 

 now the best reasons for believing are to be found far below the 

 base of the Cambrian. 



[Additional facts and illustrations, and references to previous 

 papers on the subject, will be found in " Specimens of Eozoon 

 Canadense," pp. 106, published by the Peter Eedpath Museum 

 (Notes on Specimens, Sept. 1888), which may be obtained on appli- 

 cation to the Museum, or through W. Foster Brown, Bookseller, 

 Montreal. See also, for a popular summary, Chapters v and vi of 

 " Some Salient Points in the Science of the Earth," London, 1893.] 



[For Parts I and II of this article see Geol. Mag. 1895, Dec. IV, Vol. II, 

 No. X, October, p. 443, and No. XI, November, p. 502.] 



Ekratum. — November Number, p. 503, line 30, for Aruprion read Arnprior. 



IV. — Zonal Divisions of the Cakboniferous System. 

 By E. J. Garwood, M.A., F.G.S., and J. E. Marr, M.A., F.R.S. 



||NE of us remarked last year in an article in Science Progress 

 that *' we may expect to find our Carboniferous deposits 

 divisible into zones in a manner comparable with that which holds 

 good among other . . . strata." The same writer called attention to 

 the fact that similar views had been expressed by Waagen (Salt 

 Eange Fossils, "Memoirs of the Geological Survey of India, 1891 "), 

 who considered that the Carboniferous fossils had not received the 

 same attention as those of other rocks. 



In Russia, three important divisions of the Carboniferous have 

 been made out: the stage oi Productus giganteus and Spirifera Kleini, 

 referred to the Lower Carboniferous ; and the Moscovian stage, with 

 Spirifera Mosquensis, and the Gshellian stage, with Chonetes UraJica, 

 to the Upper Cai'boniferous. The marine type of Upper Carboniferous 

 deposits has now been found widely distributed over Europe, Asia, 

 Africa, and America, though represented by few truly marine beds 

 in Britain ; but the Lower Carboniferous strata are admirably repre- 

 sented in our country, and it is the object of this paper to induce 

 local observers to pay greater attention to these beds than they have 



