REPORT ON FORESTS. 197 



during the time when this formation was being laid down, but 

 in the West the conditions were different and the remains of 

 Upper Cretaceous plants are abundantly preserved in the Lara- 

 mie and allied formations. In these most of the Middle Creta- 

 ceous genera continue, but the species, in all except a few 

 instances, are different. A large number of new genera make 

 their appearance, including one entirely new type of vegetation 

 the fan palms and for the first time the monocotyledons 

 assume some prominence. 



Generically it was more closely related to the living flora of 

 the middle United States than was that which preceded it. 

 The number of living genera included in it was actually and 

 relatively greater and the species are of a more modern aspect, 

 but none of the latter is apparently identical with any now in 

 existence. 



The ratios between the pteridophytes, gymnosperms and 

 angiosperms were apparently approximately as we find them to 

 be to-day, and the climatic condition indicated was warm- 

 temperate. 



NEOZOIC TIME. 



Tertiary Period, During the early part of this period the 

 indications are that while minor oscillations of level occurred, 

 the previous era of subsidence continued until the shore-line 

 advanced inland beyond the old Cretaceous border, covering the 

 entire coastal plain with the deposits which we know in the 

 aggregate as the Yellow Gravel formation. In places this is 

 undoubtedly of marine origin, in others it is apparently due to 

 floods of fresh water. 



At one locality only, in the vicinity of Bridgeton, has the 

 vegetation of any portion of this period been found within the 

 borders of the state. Fortunately the remains there preserved 

 were collected in considerable abundance and in an excellent 

 state of preservation. Probably about fifty species are repre- 

 sented in the collections which have been made all of them 

 angiosperms, many of them referable to living species and some 



