6 University of California Publications in Zoology [ VoL - 12 



Baird's type of Bernicla occidentalis (coll. U. S. Nat. Mus. no. 5994) 

 from Port Townsend, Washington, has been available for comparison 

 with these Alaskan specimens, and in general it may be said that all 

 appear to belong to the same race. The differences are (1) that the 

 type specimen has a faintly indicated trace of a white half collar at 

 the base of the neck, which none of the Alaskan birds possesses; (2) it 

 has a more nearly continuous, line of black spots separating the white 

 cheek patches ; (3) it is of a more reddish brown color ventrally. These 

 are all differences which, judging from more extensive series of other 

 subspecies of canadensis, may well be due to individual variation, and 

 altogether the Alaskan birds appear to be sufficiently like the type of 

 occidentalis to justify the application of that name to the breeding 

 birds of the regions where they were secured. Of the Alaska series 

 the Prince William Sound birds are smaller and darker than those 

 from the Sitkan district. The type of occidentalis is rather more 

 reddish brown below than any of the others, the effect being produced 

 by the broad tipping of cinnamon on the broccoli brown feathers of 

 the underparts. 



From typical canadensis all of these northwest coast birds differ 

 in their exceedingly dark coloration, and although there is some 

 variation in the specimens from different regions, as indicated above, 

 it is nothing compared with the gap between the darkest canadensis 

 and the palest occidentalis at hand. 



In descriptive literature treating of the subject (Ridgway, 1884, 

 pp. 456-459; 1887, pp. 116. 117; Coues, 1903, pp. 902, 904-906; etc.) 

 stress has been laid upon the presence of the white collar at the base 

 of the black neck, and the black line on the throat dividing the white 

 cheek patches, these being generally cited as distinguishing characters 

 of the race occidentalis. In the type of the subspecies the white half 

 collar is barely suggested, and the black on the throat is merely a 

 string of disconnected black spots. Of the Alaskan specimens, not one 

 shows even a single white feather at the base of the neck, and while 

 the black throat bar is in three cases faintly indicated by a few black 

 spots, in the remaining five there is not a mark to interrupt the con- 

 tinuity of the white cheek and throat patch. . Thus these supposedly 

 Characteristic markings are shown to be no more constantly present 

 in the race occidentalis than they are in true canadensis, where a sug- 

 gestion of such markings occasionally occurs. 



Judging from our specimens and taking birds of the Sitkan dis- 

 trict, Alaska, as typifying the subspecies occidentalis. the distinctive 



