30 
flora denotes a more humid environment than does the flora of the Lower 
Blairmore. 
It is curious that no traces of the dinosaur remains so characteristic 
of the Morrison and Arundel formations have been found in the Kootenay, 
since in the Arundel particularly they are associated with a flora very 
similar to that of the Kootenay. No one, it seems to me, can seriously 
question the Lower Cretaceous age of this, or any other known flora of the 
Kootenay. Lower Cretaceous floras in general contain many surviving 
Jurassic types, and the change from a Jurassic to a Cretaceous facies is 
gradual and does not become marked until the closing stage (Albian) of 
the Lower Cretaceous, by which time many of the older Mesozoic types 
have become extinct and considerable numbers of angiosperms have made 
their appearance. 
The Kootenay flora lacks the following genera that are found in the 
Patuxent formation of Maryland and Virginia, which formation I have 
correlated with the Neocomian stage of Europe; using the Neocomian in 
the restricted sense as comprising the two sub-stages Valanginian and 
Hauterivian, and not as coterminous with the sub-cretaceous of Gumbel 
(1881), the Eocretaceous of DeLapparent (1906), the Palseocretaceous of 
Kilian (1907), or the Eocretaceous or Neocomian of Haug (1908): Schi- 
zaeopsis, Ruffordia, Dryopterites, Aspleniopteris, Taeniopteris, Thinn- 
feldia, Cycadeoidea, Ctenopteris, Ctenopsis, Zamiopsis, Laricopsis, Sequoia, 
and Cedrus. It lacks representatives of the following genera that occur 
in the European Wealden: Androstrobus, Anomozamites, Recklesia, Cyca- 
deoidea, Matonidium, Mierodictyon, Otozamites, Pagiophyllum, Ruffordia, 
Taeniopteris, Weichselia, Cedrus, Laccopteris, Hausmannia, Lomatop- 
teris, and Lonchopteris. 
The accompanying table of distribution of the forms identified in the 
present study shows that eleven of them are common to the Kootenay of 
other areas and six occur in the Bull Head Mountain sandstone; six in the 
Lower Blairmore; eight in the Knoxville of the Pacific Coast region; five, 
more or less doubtfully, in the Lakota; and three in the Fuson formation 
of eastern Wyoming; five in the Patuxent and Arundel, and four in the 
Patapsco formation of the Potomac group of the Atlantic Coastal Plain. 
Five are probably present in the Kome beds of western Greenland; and 
four in the Lower Cretaceous of Europe. The only species common to 
the Jurassic or Upper Cretaceous is the composite species, Podozamites 
lanceolaius, which lacks both botanical and chronological significance. 
Although it is not to be expected that its limits are exactly the same, 
I regard the Kootenay as in the main synchronous with the Barremian 
stage of the European time scale; that is as representing approximately 
the same time as the Wernsdorf beds of Austria, the Urgonian plant beds 
of Portugal; the Klin sandstone of Russia; and the Kome beds of western 
Greenland. The lower limit of the Kootenay appears to be slightly older 
than the base of the Lakota formation of the Black Hills in eastern Wyo- 
ming, although the two are partly equivalent. No part of the Kootenay 
appears to be as young as the Fuson formation of the Black Hills; and the 
Kome beds of Greenland, which may be in part as old as the Kootenay, 
are in part younger, and their flora is more nearly comparable with that 
found in the Lower Blairmore. 
