INTRODUCTION. XXX1 
equivalents, because it is believed ‘‘that much more extensive 
studies of these formations ought to be made before any such 
correlation can be satisfactorily established.”’? 
Referring to Newberry’s discovery of Potomac species in the 
Kootanie beds of the Great Falls of Missouri river in Montana, 
White points out that, although some of the plants may be 
identical, it is certain the waters in which the two formations 
were deposited were geographically widely separated.” 
CANADA. 
In a table of correlation given by Newberry * in a paper on the 
Cretaceous floras of North America, he places the Kootanie plant- 
bearing beds of Canada on the same horizon with the European 
Wealden. Dawson‘ considers these beds as representatives of the 
Urgonian or Neocomian series; he compares them to the Kome 
beds of Greenland. There are, however, no typical Wealden 
plants included in Dawson’s list; a comparison is made between 
Salisburia (Ginkgo) lepida, Heer, and certain leaves described by 
Dunker from the Deister Wealden, but no reference is given to 
indicate what particular leaves are referred to. The only plant- 
beds of America with which Dawson compares the Kootanie fossils 
are some in Maryland, in which Tyson discovered large Cycadean 
stems and which he referred to a Wealden age.° 
JAPAN. 
In 1877 Geyler® described and figured twelve species of 
‘*Jurassic’”’? plants from the valley of the Tetorigawa in Kaga, 
1 Bull. U.S. Geol. Surv. No. 82, p. 208. 
2 Ibid. p. 252. 
3 Trans. N. York. Ac. Sci. vol. v. 1885-86, p. 135. 
¢ Trans. R. Soe. Canada, vol. iii. 1885. 
5 Ibid. p. 18. 
© Palzontographica, vol. xxiv. p. 221. 
