STATE HORTICULTUKAL SOCIETY. 367 



Texaniis, Steud,, Eriocom% cuspidata, Nutt., and several species 

 of Triticum^ complete the list of grasses collected. 



Only two species of ferns werd observed, a Woodsia and Pellcm 

 utropurpurea, Link., the latter growing in the crevices of the rocky 

 ledges on the summit of the buttes. A few mosses were seen, and 

 two species of lichens. 



The arboreal vegetation was, as might be supposed, very 

 scanty. Aside from the timber on the Missouri river bottoms, only 

 a few stunted willows, cottonwood, box-elder and Juueberry were 

 found scattered at intervals along the streams. 



A curious feature of the country west of the Missouri, beyond 

 the limit of the drift, was the great number of fossil tree stumps, 

 protruding through the sod. Hundreds could be counted in many 

 places, and in some localities, especially in Pyramid Park, the fos- 

 sil trunks were found where they had fallen, almost whole and bat 

 little the worse for the ravages of time. There is no doubt that 

 during the Cretaceous and Tertiary periods extensive forests flour- 

 ished in this region; and to judge from the size of the stumps re- 

 maining, some of the trees must have been of immense size. Many 

 stumps were seen ten feet or more in diameter, and I heard of 

 others still larger. 



This region will 3-et prove a mine of wealth to the botanist 

 stud3dng our fossil flora. Fossil leaves in great abundance occur 

 everywhere in the Tertiary sandstones and soft Cretaceous clays. 

 In some places the clay beds were originally underlain by seams of 

 lignite, which have been burned, baking the clay above into a kind 

 of brown, red, or yellow brick, which shows perfectly the forms 

 and venation of these fossil leaves. The region is well J worth the 

 time and attention of working botanists, both in recent and fossil 

 botany; and will doubtless ere long receive its 'due share of ex- 

 ploration and study, since it has become so easy of access. 



