170 M. D. F. UDVARDY 



Lunda cirrhata are amphipacific species in on only the North American sidePhalacro- 



Beringia. corax auritus (also inland), P. penicillatus, 



Eight species of marine birds are associated T ., . ,. , ,, ., , , v , D . A1 



_ .,. _ , Larus occidentals (albeit barely), and Pty- 



with the North Pacific. Four are found on 



both sides of the ocean-Oceanodroma fur- choramphus aleuticus. 



cata, Brachyramphus marmoratus, Synthli- Finally, one species, Larus thayeri, is en- 



boramphus antiquus, and Cerorhinca mono- demic at the central Canadian Arctic, extend- 



cerata (very disjunct). The four others occur ing westward into the area here considered. 



