CRETACEOUS PERIOD. 469 



North Carolina, and sparingly in South Carolina. But more to the westward, 

 at Macon, Georgia, commences the large Southern Cretaceous region, which is 

 continued into the Mississippi basin, and whose inner outline passes by Columbus 

 in Georgia, Montgomery in Alabama, and then bends northward over north- 

 western Mississippi towards the mouth of the Ohio; it descends southward 

 again on the west side of the Mississippi over eastern Arkansas, spreading at 

 the same time westward south of Little Rock and Fort Washita; not far from 

 the last point the Cretaceous area expands southward over part of Texas, and 

 northward over a large part of the eastern slope of the Rocky Mountains, as 

 already mentioned. About the summits of the Rocky Mountains, Cretaceous 

 beds occur in New Mexico along the Rio Grande del Norte to its head-waters; 

 and west of the summit they spread over the region of the Colorado as far as 

 the meridian of 113° W. 



On the Pacific coast, Cretaceous rocks have been found on the east side of Van- 

 couver's Island, and on some neighboring islands ; also, according to Whitney, 

 at various points in the Coast Range in California and along the foot-hills of the 

 Sierra Nevada, from Placer county to Shasta; they contain beds of coal on Van- 

 couver's Island and in California; part of the California rocks are metamorphic. 



As the Cretaceous formation is most fully represented in the region of the 

 Upper Missouri, a detailed section of it, by Meek & Hayden, is here given, be- 

 ginning below : — 



1. Earlier Cretaceous. 



1. Dakota group. — Yellowish, reddish, and Whitish sandstones and clays, 

 with lignite and fossil Angiospermous leaves : thickness, 400 feet. Lo- 

 cation, near Dakota, and reaching southward into northeastern Kansas. 

 This division may require to be united with No. 2 (M. & H.). 



2. Benton group. — Gray laminated clays, with some limestone : thickness, 

 800 feet. Location, near Fort Benton, on the Upper Missouri, also below 

 the Great Bend ; eastern slope of the Rocky Mountains. 



3. Niobrara group. — Grayish calcareous marl : thickness, 200 feet. Loca- 

 tion, Bluffs on the Missouri, below the Great Bend, &c. 



2. Later Cretaceous. 



4. Pierre group. — Plastic clays : thickness, 700 feet; — middle part barren of 

 fossils. Located on the Missouri near Great Bend, about Fort Pierre 

 and out to the Bad Lands, on Sage Creek, Cheyenne River, White River 

 above the Bad Lands. 



5. Fox Hills group. — Gray ferruginous and yellowish sandstones and are- 

 naceous clays : thickness, 500 feet. Location, Fox Hills near Moreau 

 River, above Fort Pierre near Long Lake, and along the base of Big 

 Horn Mountains. 



In New Jersey, the beds and their relations to those of Nebraska are thus 

 stated by Meek & Hayden from the observations of G. H. Cook : — 



1. Earlier Cretaceous ?. — No. 1 ? Bluish and gray clays, micaceous sand, 



with fossil wood and Angiospermous leaves : thickness, 130 feet or more. 



2. Later Cretaceous. — Nos. 4 and 5. (a.) Dark clays (130 feet), overlaid 



by (b.) the first bed of Green-sand, 50 feet thick. — No. 5. (a.) Sand colored 

 by iron, 60 to 70 feet; (6.) second bed of Green-sand, 45 to 50 feet; 

 (c.) yellow limestone. 



