14 MESOZOIC FLORAS OF UNITED STATES. 



stratigraphical and the paleontological points of view. It was my 

 intention at that time to improve the first o^Dportunit}^ that presented 

 itself to conduct a much more extensive campaign into that region. 

 I found the countrj^ so exceedingly dry in November that I imagined, 

 and indeed was told by persons who live there, that spring would be a 

 much more advantageous season for such a campaign. I therefore 

 decided to make a somewhat exhaustive study of this region, with an 

 appropriate outfit, in the months of May and June, 1901. 



The discovery that I made on November 14, 1899, of fossil l^ones 

 near Tanners Crossing of the Little Colorado (see first paper, pp. 322-323) 

 seemed to make it one of the prime requisites of such an expedition 

 that it be accompanied by a competent vertebrate paleontologist, 

 well versed in the methods of collecting and preserving fossil bones. 

 When the attention of Prof. H. F. Osborn was called to this subject 

 he manifested a livelj'' interest in it and offered to select a suitable person 

 to accompany me for this purpose. The choice fell upon Mr. Barnum 

 Brown, of the American Museum of Natural History, whose success 

 as a collector of fossil vertebrates and as a field naturalist in general 

 has secured for him wide recognition. The United States National 

 Museum, being in need of a series of Triassic bones, assumed the respon- 

 sibility for this part of the expedition. The rendezvous was at Hol- 

 brook, Ariz., on May 7, where an adequate outfit was procured and the 

 expedition started on the 8th. The route followed was nearh" the same 

 as that pursued by me in 1899. 



The object was to make as complete a study as possible of the 

 geology and paleontology of the Little Colorado Valley, as it is in that 

 valley, or at least in that drainage, that nearlj^ all the older Mesozoic 

 of this part of Arizona is to be found. 



Certain signs of the occurrence of Triassic vertebrates made them- 

 selves known at different points along the route, but only as weathered 

 out on the surface in such a manner that their original source could 

 not be traced. But as soon as we reached the region of variegated 

 marl buttes, some 5 or 6 miles above the Lees Ferry road, such bones 

 began to be found and their position in the beds located. Nearly three 

 weeks' careful investigation of the entire region in which such beds 

 occur proved that the small group of buttes in which I first found the 



