528 F. H. Knowlton — Shidy of the Coal-bearing Boohs 



material studied by both Lesquereux and Newberry, together 

 with splendid recent collections brought together by Lee, Rich- 

 ardson, St. John, and others, the whole making, perhaps, the 

 largest and most complete collection ever assembled for any 

 Rocky Mountain area. The results of this study are seem- 

 ingly conclusive. 



The full discussion of this flora from the biological stand- 

 point, together with diagnoses and illustrations of the species, 

 will appear in a report by Lee and Knowlton now in prepara- 

 tion. This report is so far completed as to permit the follow- 

 ing statement to be made : 



The total flora of the Raton Mesa region comprises 257 forms, 

 of which number 106 belong to the lower, or Vermejo and 

 Trinidad formations, and 151 to the upper, or Raton formation. 

 Only 4 species have been found to cross the line of the uncon- 

 formity, which is taken as pretty conclusive evidence of the 

 distinctness of these two formations. 



Taking now the flora of the Vermejo formation, with its 

 total of 106 species, it is natural first to compare it with the 

 Laramie of the Denver Basin. It is found, however, that there 

 is only one species in common to the two areas, which is negligible 

 when it is recalled that the Laramie flora comprises about 97 

 species, and, as stated above, the Vermejo 106 species. The 

 Laramie of the Colorado Springs area has three or four species 

 common to the Vermejo flora, but even this number is too small 

 to be of importance. 



The Vermejo flora is found to have an intimate relation with 

 the Mesaverde (Montana) on the west side of the mountains, 

 in fact, it is demonstrated that about 90 per cent of this flora 

 enjoying an outside distribution occurs either in the original 

 Mesaverde near Durango, Colorado, and its stratigraphic equiv- 

 alents within this area, or in beds of similar age at Point of 

 Rocks, and the Laramie Plains, Wyoming, at Coalville, Utah, 

 etc. Therefore, the Vermejo flora is regarded as being of 

 Montana age and in the approximate position of the Mesaverde. 



The Raton formation, that is, the beds above the unconform- 

 ity, may now be considered. Of its 151 species only 5 are 

 found to be common to the Laramie of the Denver Basin, 

 which shows that this relationship is remote. With the Ara- 

 pahoe there are 4 species in common w T ith the Raton flora, all 

 of them occurring also in the overlying Denver formation. 

 With the flora of the Denver formation, however, the relation 

 is very different, for of its 98 described species about 40 are 

 found in the Raton flora. This means that over 40 per cent 

 of the described Denver flora is found also in the Raton flora, 

 and when the large collection accumulated in recent years from 



