Geological Papers. 79 



weathered exposure a very rugged, honeycombed appearance. The 

 outcrop of these Nevas is very conspicuous around Bloody, 

 Spring and Jacobs creeks. On the west side of Jacobs creek, in 

 section 14, the lower Neva is exceedingly rough and honeycombed 

 in appearance. As we go south this continues throughout a num- 

 ber of sections, and then it appears much more homogeneous in 

 character, to again become rugged and change its lithological 

 characteristics. The changes in the various limestone formations 

 from the head of Jacobs creek to the south line of the state, both 

 above and below the Cottonwood, are very noticeable and exceed- 

 ingly interesting. However, they maintain a constant vertical .re- 

 lation. Across a very level plane extending east through section 2, 

 township 21, range 9, it is impossible to follow the outcrop of the 

 Cottonwood limestone, but by its relation to the limestones above 

 and below it may be mapped, since south of this point the forma- 

 tions are identical with those north of it. The Cottonwood lime- 

 stone is normal in appearance where exposed, except the upper 

 part seems to have become much softer and to have disintegrated 

 more readily, consequently giving very little escarpment. Where 

 the limestone could be seen in the ditches the Fusulina were 

 found in large quantities in their proper place, and serve as an ex- 

 cellent means of locating the formation. Where the Verdigris 

 river has cut back to the west, and the formations above the Cot- 

 tonwood are exposed, its outcrop becomes normal. The dip to the 

 south from section 31, township 20, range 10, is quite noticeable, 

 being between 1° and 2°. In section 11, township 21, range 9, 

 near a windmill, the Cottonwood lime has been quarried, and ap- 

 pears normal, save near the bottom of it, where it is noticed to be 

 somewhat molluscan (containing shells of Mollusca). For some 

 distance here the Cottonwood appears normal. In the northeast 

 quarter of section 27, township 21, range 9, it has lost many of its 

 normal characteristics. The molluscan layer has increased greatly 

 in size until about one-half of it is of this character. The Fus^i- 

 lina seem to be few; the lime is blue in appearance, though the 

 texture is the same; the hardness normal. The Fusulina layer 

 eeems to have become very soft on account of the addition of mud 

 in its formation. Where seen it is very rotten, and blue in color. 

 Some layers are seen in the formation that when broken have a 

 crystalline appearance, and are much harder than the normal Cot- 

 tonwood. At the head of a deep ravine in section 22, township 21, 

 range 9, where the talus has recently tumbled down in massive 

 boulders on the underlying shale, there are about two feet of mas 

 sive stone, very much like the lower layer of the Cottonwood, ex- 



