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 constitutes 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: (1) Forms identical with or most nearly like Pacific coast types; (2) Forms about intermediate between representatives inhabiting the Pacific and Middle Provinces; (3) Forms to a certain extent intermediate between Pacific and Middle Province representatives, but differing from both in certain original characteristics. 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 majority 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 difficulties in the way of its satisfactory presentation. I refer to the naming of these intermediate 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, however, is not likely to be remedied, for it is difficult to conceive of a system of nomenclature that would adequately designate the 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 examining the matchless series in the National Museum, and to whom I am further indebted for many valuable suggestions. My obligations to Capt. Bendire are greater than I can adequately express, for, in addition to other kind attentions, he has generously presented me with many valuable specimens included among those about to be discussed.
List of Species and Varieties represented in the Collection.
1. Turdus migratorius.[[102]] 2. Turdus migratorius propinquus. 3. Sialia arctica. 4. Myiadestes townsendi. 5. Regulus satrapa olivaceus. 6. Parus atricapillus occidentalis. 7. Telmatodytes palustris paludicola. 8. Anthus ludovicianus. 9. Lanius borealis. 10. Ampelis garrulus. 11. Ampelis cedrorum. 12. Hesperophona vespertina. 13. Chrysomitris tristis. 14. Passerculus sandvicensis alaudinus. 15. Zonotrichia gambeli intermedia. 16. Spizella monticola ochracea.[[103]] 17. Junco oregonus. 18. Melospiza fasciata guttata. 19. Pipilo maculatus megalonyx.[[104]] 20. Agelæus phœniceus. 21. Sturnella neglecta. 22. Scolecophagus cyanocephalus. 23. Corvus americanus.[[105]] 24. Pica rustica hudsonica. 25. Cyanocitta stelleri annectens. 26. Eremophila alpestris.[[106]] 27. Picus pubescens gairdneri. 28. Melanerpes torquatus. 29. Colaptes auratus hybridus.[[107]] 30. Colaptes auratus mexicanus. 31. Ceryle alcyon. 32. Asio americanus. 33. Asio accipitrinus. 34. Scops asio kennicotti.[[108]] 35. Bubo virginianus subarcticus.[[109]] 36. Bubo virginianus saturatus. 37. Nyctea scandiaca. 38. Falco columbarius suckleyi. 39. Falco richardsoni. 40. Falco sparverius. 41. Accipiter fuscus. 42. Astur atricapillus. 43. Astur atricapillus var. ——?[[110]] 44. Buteo borealis calurus. 45. Buteo swainsoni. 46. Archibuteo lagopus sancti-johannis. 47. Archibuteo ferrugineus. 48. Zenaidura carolinensis. 49. Bonasa umbella sabinii. 50. Pediœcetes phasianellus columbianus. 51. Charadrius dominicus.
Species and Varieties calling for Special Consideration.
6. Parus atricapillus occidentalis (Baird) Coues. Oregon Chickadee.—A series of six specimens furnishes satisfactory proof—which I believe has been heretofore wanting—that P. occidentalis is simply a dark, geographical race of P. atricapillus. One example is absolutely typical of occidentalis, while the others grade evenly into a form that is essentially undistinguishable from atricapillus. Indeed the lightest colored specimen is so nearly like some Massachusetts birds taken at the same season that I have been unable, after a most careful comparison, to detect the slightest difference in either color or markings: the wing of the Walla Walla skin, however, is slightly shorter. There are no apparent approaches in this series to P. septentrionalis.
16. Spizella monticola ochracea var. nov. Western Tree Sparrow.—Ch. Subsp. ♂ ♀ Similis S. monticolæ, sed colore suprà dilutiore; strigis dorsalibus rarioribus, angustioribus et magis acutè in tergo pallidiore depictis; lateribus gulâque magis ochraceis; vertice, in auctumnalibus quidem avibus, sæpissimè magis cinereo.
♂ (Fort Walla Walla, Washington Territory, Nov. 8, 1881. Capt. Bendire.) Back and rump pale sandy-brown or brownish-ochraceous, the back with sharply defined black streaks which, excepting on the scapulars, have no chestnut bordering; crown invaded centrally, from the nape, by a broad space of pale ash which tinges most of the feathers to their bases and confines the usual chestnut to a small area on the forehead and two narrow, lateral stripes; lores and sides of head pale fulvous; entire under parts washed with warm ochraceous, deepest on the sides and abdomen, palest on the throat where it only partially conceals the ashy beneath. Otherwise similar to S. monticola.