P^RT III. 



THE CRETACEOUS FLORA. 



In continuation of the plan of this series as outUned in the introduc- 

 tory remarks to the first paper, the treatment of the Triassic flora (Part I) 

 and the Jurassic flora (Part II) having been completed and ah available 

 information with regard to them having been brought down to date (close 

 of the year 1903), the Cretaceous flora (Part III) may now be taken up. 

 In endeavoring to treat the Cretaceous in strict geological sequence, 

 beginning with the lowest, one is troubled by the fact that at least five of 

 the Lower Cretaceous floras begin so near the base of that system that they 

 practically constitute a transition from the Jurassic to the Cretaceous. 

 These are the Shasta group (Knoxville beds), the Kootanie group, the 

 Lakota group, the Trinity group, and the Older Potomac (James River 

 beds). In view of this practical stratigraphical synchrony it becomes 

 necessary to adopt some geographical order, and as the only Jurassic flora 

 thus far known occurs on the Pacific slope, and especially as the Francis- 

 can or Golden Gate formation last considered seems to form a passage bed 

 in that region from the true Jurassic to the true Cretaceous, it seems most 

 logical to begin with the Shasta group. It wiU then be most natural to 

 work eastward and consider the Kootanie of Montana, the Lakota of the 

 Black Hills, and the Trinity of Texas, closing with the Potomac of Virginia 

 and Maryland. 



LOWER CRETACEOUS FLORA OF QUEEN CHARLOTTE ISLANDS. 



It is perhaps worth while to mention that certain beds in the Queen 

 Charlotte Islands which have yielded fossil plants seem to occupy practi- 

 cally the same horizon as those mentioned above and have been correlated 

 with both the Shasta group and the Kootanie. These beds were dis- 

 covered by Mr. James Richardson in 1872 and he made extensive collec- 

 tions of both the fauna and the flora. His report is to be found in the 



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MON XLVIII — 05 14 



