INTRODUCTION. 



As this work will in all probability fall into the hands of those who have 

 not seen the ornithological volume issued as a part of the Publications of the 

 State Geological Survey of CaUfornia, it is proper that the origin and connection 

 of these two contributions to this branch of American natural history should 

 be here explained. 



The Act authorizing a geological survey of the State of California, which 

 became a law in 1860, required of the State Geologist, in addition to the 

 topographical and geological work usually expected on such a survcv, " a full 

 and complete description of the botanical and zoological productions of Cali- 

 fornia." In accordance with this requirement, the efforts of the head of the 

 Survey were, from the time of the beginning of the wijrk, directed toward the 

 collection of such material as would be of value for use in the preparation of 

 Eeports in the various departments of the natural history of California and the 

 adjacent regions of the Pacific coast. The establishment of a State museum 

 of geology and natural history was also contemplated — although not provided 

 for — in the Act authorizing the Survey, as supplementary to the preparation of 

 such Reports on the various bi'anches of science as should make possible the 

 study of geology, botany, and zoology in the schools and colleges of California 

 and the adjacent States and Territories. 



The Survey as thus organized went on without interruption until 1868, 

 when appropriations were withheld fur two years ; but the work was not brought 

 to an absolute stoppage, all the materials having been left in the hands of the 

 State Geologist, without any direction as to what was to be done with them, 

 and also without any appropriation of money to pay either for the care and 

 preservation of collections then on hand, or for the continuation of publications 

 at that time actually in progress. 



Nevertheless the work did go on ; and among the volumes completed during 

 the stoppage of the Surs-ey was one on which considerable progress had been made 

 at the time the apjjropriations were suspended. This volume belonged to the 



