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 Jan.,1914 SECOND LIST OF BIRDS OF THE BERKELEY CP, MPUS 29 the stream-courses are lined with bay (or California laurel), alder, and willow. Clumps of bay occur in the heads of the upper ravines and even on the crests of the highest hills. 'l'he prevalent tree over the whole .Campus is the live-oak, which reaches large dimensions on the lower Campus, and occurs in smaller size mixed with the chaparral of the lower hill-slopes. T'he upper, hilly portion of the Campus consists chiefly of truly "wild" land, save as the open parts have been pastured over for many years. This element of wildness accounts for the occurrence of many of the less familiar species of birds. Then on the lower Campus, the growth of planted groves, and gardens, has added to the native features attractive to bird-life. In spite of ths, however, there has been a notable decrease in the past six years in the aggregate native bird popula- tion. 'Phis is partly accounted for by the building up closely of the lower and more level country (and to this extent it is inevitable), and partly by the ravages of house cats and the increase of the English Sparrow. Number of birds to be seen at any one time is pretty constant. A daily "horizon", that is, the number of species noted in the course of one day's or part- day's observation, consists ordinarily of 2o to 24 species. On July 3, 199, the writer recorded 29 species; on February II, 1911, 26 species; on March 25, 1911, 22 species; on January 2o, 1912, 20 species. On October 18, 193, a four hours census showed 27 species and 41o individuals. There is little evidence of the semi-annual migratory movement of the birds, so conspicuous in some parts of the United States. Our list of transient species is short, and relatively very few individuals of any of the non-resident categorie., are through migrants; the summer visitants and the winter visitants, in each case, simply arrive scatteringly to stay for the season, and their departure is so grad- ual as to often go unnoticed. From a distributional standpoint, the Berkeley Campus is situated in the Up- per Sonoran life-zone, with a marked Transition or even Boreal infusion notice- able particularly in the summer-visitant category of birds. Of the latter are tO be listed the Olive-sided Flycatcher, Western Wood Pewee, Cassin Vireo, Tolmie Warbler, and Alle tlummingbird. The resident Coast Jay, Pine Siskin and Nuttall Sparrow are typically birds of the cool ht'..mid coast strip of Ca!ifornia. It looks as though the amount of the gap in the continuity of the coast fauna at Golden Gate were simply transported to the eastward across the bay by the pre- vailingly west winds and deposited on the west-facing slopes adjacent to Oakland and Berkeley. The writer's cordial acknowledgments are hereby extended to Mrs. Amelia Sanborn Allen, Mrs. Hilda Wood Grinnell, Miss Margaret W. Wythe, Dr. Harold C. Bryant, Mr. 'l'racy I. Storer and Mr. Harry S. Swarth, for notes and records furnished by them. It is chiefly because of the contributions from their stock of information, as recorded in their field note-books, that the writer is able to furnish the accompanying annotations. Initials are used to designate responsibility for specific records. Classified seasonally we find that 33 of our birds are permanent residents, :el are summer visitants, 29 are winter visitants and 14 are transients. A total of 97 species is now accredited to the Berkeley Campus, as against 76 three years ago. It is estimated that a mean population of approximately 8o0o individual bi?ds is maintained throughout the year within the area here treated. Because of the arbitrary limitation of the present list to those species which have been seen on the University grounds, a number of well-known birds of the San Francisco Bay region are notably missing. Many of these, such as the Barn