ROCKS SOUTH OF THE FORTY-NINTH PARALLEL. 303 



measures, are exposed at the mouth of the Platte *, and 

 extend up the river about fifty miles, when they dip be- 

 neath the water level of the Missouri. They are overlaid 

 by No. 1 of the Nebraska section of the Cretaceous Series 

 in lat. 41°-5, long. 96°. Cretaceous and Tertiary for- 

 mations then occupy the valley of the Missouri as far as 

 Fort Benton, lat. 47 0, 54, long. 110°, and extend into 

 British America. Hence it appears that, ten degrees of 

 latitude south of the Biding Mountain, the Cretaceous 

 Series repose on the Carboniferous without the inter- 

 vention of Permian, Triassic, or Jurassic rocks. 



In Kansas territory, on the Kansas and Smoky Hill 

 Bivers, an elaborate section has been made by Messrs. F. 

 B. Meek and F. V. Hayden f, commencing with the Cre- 

 taceous sandstones on the summit of the Smoky Hills, 

 lat. 38° 30' K, long., 98° W., and descending through 

 the various intermediate formations seen along the Smoky 

 Hills and Kansas Biver to the mouth of the Big Blue 

 Biver on the Kansas. This section, over 1000 feet 

 vertically, passes from the Cretaceous to the upper coal 

 measures, and includes rocks of Permian age. Messrs. 

 Meek and Hayden remark, in relation to this section, " It 

 will be observed we have in this general section, without 

 attempting to draw lines between the systems or great 

 primary divisions, presented in regular succession the 

 various beds with the fossils found in each, from the Cre- 

 taceous sandstone on the summits of the Smoky Hills, 

 down through several hundred feet of intermediate doubt- 

 ful strata, so as to include the beds containing Permian 



* Notes explanatory of a Map and Section illustrating the Geological 

 Structure of the Country bordering on the Missouri -River, &c, by F. V. 

 Hayden, M.D. 



t Geological Explorations in Kansas Territory, by F. B. Meek and F. V. 

 Hayden, published in the Proceedings of the Academy of Natural Sciences at 

 Philadelphia. 



