Uaj-clen.] '^^ [February 19, 



try. On our right the Laramie range appears like a wall bending round 

 to the north-west and west, and finally disapi^earing from view at Coop- 

 er's Creek Station. Near the crossing of the Big Laramie river we see 

 on our right the red beds which are somewhat marked. We can follow 

 them up to the foot of the mountains by their peculiar brick red color. 

 Then come the cretaceous rocks, especially the uijper members of the 

 groui?, soon after crossing the Laramie river, and continue to a point 

 about 5 miles east of Como Station, more than 60 miles west of Laramie 

 City. There may be some few isolated patches of the tertiary beds. 

 The principal rocks seem to belong to No. 5. 



Carmichael's Cut east of Rock Creek is a locality quite well known. 

 The strata cut through are mostly rather friable fine grained rusty gray 

 sandstones, with bluish brown calcareous concretions of various sizes 

 scattered through them, which when broken open reveal a great variety 

 of shells — Baculites, Ammonites, Inoceramus, and many other species 

 characteristic of No. 4 and 5, which undoubtedly blend throughout this 

 region, and cannot be separated as distinct divisions of the system. 

 No. 3 has not been observed along the immediate line of the railroad, 

 but it is well showed in many localities in the Laramie plains. 



From Laramie City to Cooper's Station the country as far as the eye 

 can i-each presents a cheerful appearance. The irregularities of the sur- 

 face are smoothed down and a long stretch of level prairie is covered 

 with grass, with here and there a grass covered ridge or rounded butte. 

 The basis rocks are mostly indurated arenaceous clays or loose yellow 

 sands which yield readily to atmospheric influences. There are many 

 rounded arenaceous concretions, and sometimes a thin layer of laminated 

 sandstone. There is a slight disturbance of the beds ; and the ridges 

 of upheaval seem to trend nearly east and west. 



As we proceed westward from Cooper's Station we find the black 

 clays of No. 2, and the appearance of the country becomes dreary and 

 sterile in the extreme. They extend to a point about 5 miles east of 

 Como. The waters are alkaline, and there is no timber along the creeks 

 except stinted willows, and very little grass or vegetation of any kind ; 

 as far as the eye can reach nothing but black plastic clays. 



Just before reaching Como we come to a very interesting quarry of 

 sandstone from which the materials for the construction of the extensive 

 railroad buildings at Laramie City and Cheyenne are obtained. The 

 rock is a gray, rather friable, sandstone, and occurs in isolated patches 

 resting on the shaly clays of No. 2, and are so filled with fragments of 

 vegetable impressions, sometimes quite distinct deciduous leaves, that 

 one is reminded of the tertiary sandstones. I am inclined to think how- 

 ever that it is a local deposition of sandstone in the cretaceous series. 

 This point and the district about Como is extremely interesting to the 

 geologist, and there are some curious problems yet to be solved. 



At Como Station the railroad runs for some distance through a distinct 

 anticlinal valley, the strata inclining away to each side. The south side 

 of the road exhibits the most complete series of the beds. A high ridge 



