1921] Merriam: Palaeontological Research on the Pacific Coast 249 



Brea now in progress by Chester Stock has been extended to include 

 the wliole problem of edentates on the West Coast. Other contribu- 

 tions to the study of the ungulates from the asphalt beds have been 

 made by W. P. Taylor and A. C. Chandler, while the batrachians 

 have been reported upon by C. L. Camp. 



Not the least significant of the studies in vertebrate palaeontology 

 on the West Coast are those concerning the faunas of mammal-bearing 

 deposits having a well understood stratigraphic relation to the marine 

 Tertiary series west of the Sierra Range. Especially important are 

 the collections obtained by parties working in the Coalinga region 

 under the leadership of Bruce L. Clark in 1913. Mammal material 

 secured at that time represents at least tliree important horizons of 

 the Miocene and Pliocene. These collections may with some degree 

 of satisfaction be compared with the Tertiarj^ mammal series of the 

 Great Basin region, and furnish the most valuable, evidence bearing 

 on correlation between the Great Basin and Pacific Coast formations 

 thus far obtained. 



Growing out of the work in vertebrate palaeontology west of tlie 

 Wasatch, has come an effort to construct a correlation scheme of the 

 mammal-bearing Tertiary formations of the Great Basin Province for 

 use in fuller understanding of the palaeontological sequence. The cor- 

 relation plan includes consideration of evidence of any and every 

 kind that may be used to furnish us with information concerning the 

 time relations of formations and their contained faunas. This work, 

 under way for many j'ears, can obviously never be completed. It is 

 being preseiited for publication in the form in which it stands in 1917. 

 As an outcome of the correlation it has become clear that further 

 progress in our mammal history can be advanced most quickly by 

 careful mapping and detailed study of the fauna! zones in an area 

 containing a considerable portion of the Cenozoic section. Such an 

 area is found in the John Day region of Oregon. Through cooperation 

 with the United States Geological Survey and tlie University of 

 Oregon work on a detailed monographic study of this region was 

 begun in 1916. Intensive study of a small portion of the most imper- 

 fectly understood part of the section, represented by the Rattlesnake 

 Pliocene and Mascall Miocene, has given unexpectedly large returns. 

 Continuation of this work promises the beginning of a new epoch 

 in interpretation of West American vertebrate faunas, and will greatly 

 increase the scope of our studies so far as we have relation to world 

 problems of evolution and distribution. 



