FOREWORD 



THIS monograph was accepted in candidacy for the degree of doctor 

 of philosophy at the University of Chicago in June, 1897. 



Further field-research immediately following made necessary a revi- 

 sion before publication, and this latter work has been long, but una- 

 voidably, delayed. 



I wish to acknowledge my great obligations to Dr. W. L. Jepson, of 

 the University of California, for his services in identifying my botanical 

 specimens. Many of my collections were hastily gathered, and, with- 

 out flowers or sufficient foliage, could be determined only by one espe- 

 cially trained in the desert flora of California. 



It would be a great pleasure to mention by name the many Coa- 

 huilla friends whose interest and assistance have made this study pos- 

 sible. One of them, my friend and inmate of my home, Martin Costo, 

 has read nearly the entire manuscript and made numerous corrections. 

 The proofs have been read by Dr. Merton L. Miller, of the University 

 of Chicago, and the entire essay has received the benefit of his atten- 

 tion. 



It is fitting, also, that I should acknowledge the large part that has 

 been taken in the preparation of this essay by my wife, Anna Spencer 

 Nichols Barrows. Mrs. Barrows accompanied me when much of this 

 material was secured, and her cooperation has been invaluable at every 

 point of preparation. 



D. P. B. 



MANILA, P. L, December, 1900. 



