4 PEEFATOEY NOTE. 



promoted very materially the progress of this work; he has, more- 

 over, collected several hundred phEenogamic plants of pronounced 

 value, expressly for the author's use. Mr. J. B. Davy has provided 

 a competent and much needed revision of the grasses for which the 

 author is especially grateful; he has also furnished several thousand 

 specimens, many of which were accompanied by field notes. For the 

 privileges of a research student at the G-ray Herbarium of Harvard 

 University cordial thanks are returned to Prof B. L. Bobinson. 

 Frequent use has been made of the Herbarium of the California 

 Academy of Sciences and kindly acknowledgments are due to its 

 curator, Miss Alice Eastwood. For contributions of valuable 

 specimens it is a pleasure to ,name Mr. S. B. Parish of San 

 Bernardino, Mr. R. H. Piatt of Vacaville, Mr. M. S. Baker of the 

 Sacramento High School, Mr. P. S. Woolsey of the Visalia High 

 School, Mr. J. H. Barber of Paso Eobles, and Mr. H. M. Hall, 

 Mr. H. P. Chandler, and Mr. J. P. Tracy, students of the Uni- 

 versity of California. Finally there is to be mentioned the valuable 

 assistance in proof-reading given by Mr. P. E. Goddard, Mrs. E. J. 

 0. Gilbert and Miss K. D. Jones. 



Many a valley and mountain peak of California, numerous 

 chaparral slopes and leagues wide plains have not to this day been 

 explored botanically. ' There must yet be numerous additions to the 

 knowledge of our flora before such knowledge can be considered in 

 anywise complete. Emendations and notes of omission will, there- 

 fore, be most gratefully received. 



Willis Linn Jbpson. 

 Mt. Whitney Trail, 



Aug. 6, 1900. 



