294 



FLORA OF LOWEE COAL MEASURES OF MISSOUEI. 



ern Anthracite field. It will be interesting, therefore, in a brief comparison 

 of the Missouri flora with the floras of the European basins, to note the 

 positions of our species in several of the paleobotanically better known 

 Old World Carboniferous sections. 



This task, so far as it relates to Great Britain, is made easy through 

 reference to a late publication in which Mr. Robert Kidston, the highest 

 British authority on the Paleozoic floras, has combined and tabulated the 

 results of his most valuable and interesting studies of the fossil floras of the 

 British Carboniferous rocks.^ 



In the following table is given (1) the vertical distribution by groups 

 of the species found iDoth in our Missouri flora and in Gfreat Britain, and 

 (2) the distiibution of a number of Old World species (parenthesized) 

 whose relations to our species are sufficiently intimate to lend an inferential 

 significance to their stratigraphic occiu'rence. But in drawing conclusions 

 of a chronologic nature, relatively little weight should be given to the dis- 

 tribution of the related species, whose evidence is subject to othei' and per- 

 haps more important elements of uncertainty than those of mere personal 

 opinion and interpretation of figures and descriptions. 



Table showing distrihution in the Coal Measures of Great Britain of the plants of the 

 Lower Goal Measures of 2Ussouri or of certain closely related species.'^ 



'= iileasures. 



Middle 



Co.ll 



Measures. 



Upper 



Coal 



Measures. 



Exdptdites Callijyteridis (Schimp.) Kidst 



Pseiulopecoirieris obtvsiloba (Brongn.) Ls 



Ps. squamosa (Ls.) 



Mariojyteris cf. nervosa {21. nervosa (Brongn.) Zeill.) 



M. 8phenox)ieroidee (Ls.) Zeill. (i/. acuta (Brongn.) Zeill.). 

 Mariopteris u. sp. (Sphenojjteris Jaequoii (Zeill.) Kidat.) ... 



Sphenopteris mixta .Schimp 



/S, Lacoei D. W. {S. rotundifolia Andrii) 



S. Broadheadi D^W. {Symenotheca Dathei Fot.) 



5. missouriensis J). W. (5. JVoodttiardii Kidst.) 



S. pinnatifida (Lx.) (5. quadridaciylites Gntb.) 



S. cristata (Brongn.) Presl 



-S. suhcrenulata (Ls.) (Pecopterls crenulata Brongn. j 



OUyocari>ia missouriensis D.W, (0. Brongniartii Stnv) 



' oh tlie Various Divisions of British Carboniferous Rocks as determined by their Fossil Flora. 

 Address of the retiring vice-president. Proc. Roy. Phys. Soc. Edinb., vol. xii, 1894, pp. 183-257. 



-Names of foreign related species, -whose distribution is given, are in parentheses immediately 

 following the names of the American species to vrhich they bear relation. 



