2 26 Brewster on Birds of JPort Walla Walla ^ W. T. 



As an exponent of the workings of geographical variation in 

 species easily modified by their surroundings, this material is 

 especially instructive. The region represented apparently con- 

 stitutes a sort of neutral ground between the Pacific and Middle 

 Provinces and naturally its fauna is a mixed one. Setting aside 

 species not subject to geographical modification, and migrants 

 from the north which have only an indirect bearing on the 

 general question, we find the collection divisible into three 

 classes: (i) Forms identical with or most nearly like Pacific 

 coast types ; (2) Forms about intermediate between representa- 

 tives inhabiting the Pacific and Middle Provinces ; (3) Forms to a 

 certain extent intermediate between Pacific and Middle Province 

 representatives, but difl'ering from both in certain original char- 

 acteristics. The locality seems to be nearly lacking in typical 

 representatives of the Middle Province ; and its fauna, on the 

 whole, must be regarded as closely related to that of the coast 

 region. 



The third class, although least numerous, includes many of the 

 most interesting birds. The majorit}' of these are resident forms, 

 a fact which sufficiently explains many of their peculiarities, for 

 it is well known that sedentary species are, of all others, the most 

 subject to local variation. 



But while the philosophic bearing of this material is not 

 doubtful, there are certain systematic difticulties in the way of 

 its satisfactory presentation. I refer to the naming of these in- 

 termediate forms. The practice has been to use the name of the 

 race to which the bird seems most nearly related, and this I have 

 been forced to adopt in default of a better way. But the method 

 obviously fails to meet the requirements of such cases, while to 

 a certain extent it is unscientific and inaccurate. The evil, how- 

 ever, is not likely to be remedied, for it is difficult to conceive 

 of a system of nomenclature that would adequately designate tlie 

 numberless intermediate and local types. 



In the present connection I would gratefully mention the 

 assistance received from my friend, Mr. Ridgway, who, during 

 my study of the collection, has given me every facility for exam- 

 ining the matchless series in the National Museum, and to whom 

 I am further indebted for many valuable suggestions. My obli- 

 gations to Capt. Bendire are greater than I can adequately ex- 

 press, for. in addition to otlier kind attentions, he has generouslv 



