250 W. Cross — New Devonian Formation in Colorado. 



shale division, with its casts of salt crystals, by which it may 

 quickly be recognized in nearly all localities. Especially where 

 the formation is found capping a bench or isolated knoll, as at 

 Overlook Point and several other places on the granite surface 

 north from Endlich Mesa, the thin limestone slabs covered 

 with these casts are often very abundant. As was noted by 

 Endlich, the casts were found on the unci er-surf ace of layers 

 and testify to peculiar local conditions. While commonly on 

 earthy limestone, the casts have been noted on coarse quartzose 

 sandstone. The most important variation in the lithologic 

 character of the Elbert formation is in the appearance of dense, 

 earthy limestone of conchoidal fracture, in several beds in its 

 upper portion. This development is most notable on the west 

 flank of the Needle Mountains, and also at Bluebird Park, in 

 the northwestern section of the Needle Mountains quadrangle. 



The only fossils as yet obtained from the Elbert formation 

 are fish remains, and the most productive locality discovered is 

 that of Devon Point, already described. The remains were 

 found at the base, and also very near the top of the section 

 referred to the Elbert, showing the formation to be a well 

 defined unit as to its fauna. Fish remains have also been dis- 

 covered at two other localities, to be briefly mentioned. 



At about one mile south of Rockwood, and close to the rail- 

 road track, a block of pale reddish quartzite was found at the 

 base of the talus slope, upon which were rather indistinct 

 remains of three individual fishes. The ledge of quartzite just 

 above this talus heap belongs to the Ignacio Cambrian quartz- 

 ite, but the sloping bench between that ledge and the cliff of 

 Ouray limestone some yards farther back is occupied by the 

 Elbert formation. Repeated search has failed to reveal the 

 stratum from which the fish-bearing slab came, and no other 

 remains were obtained. It is almost certain, however, that the. 

 slab in question came from a thin bed in the lower part of the 

 Elbert section. 



Another, and somewhat different, occurrence of fish remains 

 was found on Little Cascade creek, about one-half mile «outh 

 of Columbine lake and seven and one-half miles north of Rock- 

 wood. At this point the shales containing salt casts are suc- 

 ceeded by several massive limestones alternating with shaly 

 strata. Several thin layers rich in finely comminuted fish 

 scales or plates occur beneath the limestones, and in one of the 

 limestones, resting with irregular contact upon such a layer, a 

 few large plates were found. 



All the fish remains above mentioned have been examined 

 by Dr. C. R. Eastman, who, in the accompanying paper, 

 describes the fauna represented bj them and discusses their 

 interest from the paleontological standpoint. From the strati- 



