Ward — Geology of the Little Colorado Valley. 407 



cross-bedded, possesses considerable grit, and has small clay 

 pellets included in it similar to those of the true conglomerate 

 series, in which I have for this reason included it. This con- 

 dition of things may be somewhat puzzling from the strati- 

 graphical point of view, but the disadvantage in this respect 

 is much more than compensated for by the evidence that it 

 furnishes in favor of the view that all of these beds really con- 

 stitute one great system, and as opposed to the view which it 

 may be inferred that certain geologists hold, that the series of 

 beds which I have included under the name of the Moencopie 

 beds belongs to a different system, and are in some way con- 

 nected with the underlying Paleozoic rocks. This view, in 

 the light of the above mentioned facts is, in my opinion, quite 

 untenable. 



The Le Roax Beds. — Under the name of Le Roux beds I 

 include the remainder of the Shinarump, deriving the name 

 from Le Roux Wash,* which enters the Colorado Valley two 

 miles below Holbrook, and on which some 15 miles north of 

 Holbrook this series attains the greatest development that I 

 have observed, probably reaching its maximum of 800 feet. 

 These beds, too, if studied at localities where they are less 

 developed, might be supposed to form several quite distinct 

 subdivisions. Indeed I was of this opinion during most of my 

 stay in the lower Little Colorado Valley, but even before 

 leaving there the proofs of their homogeneity had become 

 abundant. 



At least the lower half consists of that remarkable formation 

 in which I found vertebrate bones in 1899 and in which alone 

 thus far vertebrate remains have been observed. I have some- 

 times designated it as the Variegated Marls, sometimes as 

 the Belodont beds. The distinguishing features of these beds 

 is the presence of great numbers of small buttes, the smaller 

 ones appearing to be blue clay knolls, but the larger ones show- 

 ing other colors, especially purple, and sometimes several bands 

 of different hues. Almost everywhere at this horizon there 

 exist plains, dotted all over with these remarkable little buttes, 

 varying from 3 or 4 feet to 20 or 30 feet in height, usually iso- 

 lated from one another and having a form peculiar to them. 

 They are not conical in the true sense of the word, since they 

 do not rise to a point at the summit, but are always rounded 

 off and have the form of a well made haystack, the smaller ones 

 looking like haycocks in a field. These butte-studded plains 

 are of course simply the remains of a plateau or mesa which has 



*The name " Leroux's Fork" was given to this wash by Lieut. Whipple's 

 party, who followed it down some distance and encamped at its junction with the 

 Little Colorado on Dec. 5, 1853, this being their Camp 79. See Pacific Railroad 

 Reports, vol. hi, part i, p. 75. The name is written in two words on the Land 

 Office map of Arizona. 



