80 ORNITHOLOGICAL EXPLORATIONS. 



It was only two years after that Bonaparte (Cousp. Avium, II, p. 22G) 

 transferred the name kotzebui to the black-legged representative of 

 tridactyla in the Pacific. 



The above conclusions were made under the supposition that " No. 

 31, hrachyrhynchus Gould," of Bruch, 1853, is not the true brachyr- 

 hynchus of Gould (which is the red-legged breviroslris Brandt, with the 

 red color of the legs faded into yellow), but the black-legged Pacific 

 representation of B. tridactyla. 



Somebody might, however, advocate that Bruch's brachyrhynchtts 

 ought to be considered the same as Gould's species, as nothing in the 

 short diagnosis really contradicts such an opinion. It might be said, 

 with all ])robability of being correct, that Bruch was under the same 

 impression as was Dr. Otto Finsch still in 1872,* viz., that R. tridactyla 

 proper is an inhabitant. of the whole northern hemisphere, and that 

 in the Northern Pacific two other Eissce occur, besides, one with yel- 

 low legs {brachyrhynchus Gould), another with red legs {brevirostris 

 Brandt). This being the case, Bonaparte's "41 nivea Pall." would 

 also become a synonym of the true brachyrhynchus Gould. In defense 

 of this opinion might be quoted Bonaparte's Conspectus Avium, in 

 which he indeed gives his No. 41 as a synonym of brachyrhynchus 

 =^brevirostris, then for the first time properly located and understood. 



This theory, if correct, would make no change in the results, above 

 arrived at, as it would only prove that both Bruch and Bonaparte were 

 wholly unacquainted with the North Pacific Kittiwake up to 1856, 

 that their numbers, 31, 32, and 41, 42, were identical, and, conse- 

 quently, lotzebuii, 1854, the synonym of brevirostris Brandt. 



As Rissa kotzebui Bp., 1856, is j) roved to be i)reoccupied, this sub- 

 species is left without a name. I, therefore, have proposed to call it 

 Eissa tridactyla pollicaris. Were it not for the inconstancy of the 

 character derived from the greater or lesser development of the hind 

 toe, the two forms would have to stand as distinct species. As the 

 case is now, they can only be recognized as subspecies. It may, how- 

 ever, be mentioned that the Pacific form does not differ only in the 

 development of the hind toe, as the black tips of the first i>rimaries 

 are longer, and the bill, on the average, longer and diflerently shaped 

 than in the Atlantic bird. Besides, I have been unable to find in any 

 specimen of a large series of pollicaris the black of the tips of the 

 second and third i)rimaries running down along the edge of the outer 

 web. 



*Abliandl. Brem. Ver., Ill, 1872, pp. 84, 85, sps. 107, 108, 109. 



