JAN 14 1203 



PREFACE. 



This paper is the result of a study begun in 1894 ^pon 

 an interesting collection of Upper Cretaceous fossils from 

 a new locality in Southern Oregon, locally known as the 

 " Forty-Nine Mine," but referred to here as the Phoenix 

 Beds. 



The special feature of interest in this collection is the 

 large percentage of individuals and species of the genera 

 Schloenbachia, Scaf kites, and the aberrant forms of cepha- 

 lopods, types for the most part that were unfamiliar upon 

 this Coast. The contents of this collection was referred to 

 in the May-June number of the Journal of Geology, 1895. 



Since the first visit to this locality almost every year has 

 added new and important species from the same place, and 

 from a quite similar locality on the opposite and southern 

 slope of the Siskiyou Range, near the village of Henley, 

 Siskij^ou County, California. These two localities evi- 

 dently belong to the same coastal basin of the Cretaceous, 

 and are here included in what is called the Oregon Basin. 



From this fauna the study was naturally led to the Chico 

 deposits of the Sacramento Valley, and from these to the 

 Horsetown and the whole of the Cretaceous. 



In offering this paper for publication the author wishes 

 to acknowledge the kindly interest and assistance of his 

 instructors and co-workers, Drs. J. P. Smith, T. W. Stan- 

 ton, J. C. Merriam, and others, who have shown not only 

 professional courtesies, but have aided the work by a 

 friendly appreciation and a cooperative spirit. 



The conclusions that have been reached by this study, 

 while they may not be final, are nevertheless believed to be 

 important in the development of our knowledge of West 

 Coast geology, and in the stud}' of the Great Past and its 

 biological and physical geography. F. M. A. 



December 17, 1900. 



( I ) Li] December 24, 1903. 



