534 Nichols and Murphy, Genus Phcebetria. Loct' 



Conclusions. 



Summarizing our conclusions on the genus Phoebetria, upon the 

 not wholly sufficient basis of the material studied, we find in the 

 first place two well differentiated species, imlpchrata and fusca, of 

 more southerly and more northerlj- distribution respectively, but 

 of coincident range in an intermediate zone. The last generaliza- 

 tion may not hold true in the eastern Pacific, where the only known 

 representative, Phoebetria palpebrata auduboni, may have become 

 part of the fauna of the northern hemisphere in accordance with the 

 general tendency' of the Diomedeidre to range northward in that 

 ocean. 



The species palpebrata is in turn divided into two main sections, 

 one of which includes only auduhom with a range west of America 

 and Weddell Sea, the other comprising the three pale subspecies 

 antarctica, palpebrata, and huttoni, ranging from west to east, 

 respectively, across the Atlantic and Indian Oceans, to the waters 

 south of Australia, and forming in the same order a decreasing 

 sequence in size. These three subspecies have a range in latitude 

 extending from the verge of the true Antarctic at least to the middle 

 of the southern temperate zone. It seems possible that the ranges 

 of huttoni and auduboni may be separated by the vast stretch of 

 the southern Pacific, where the little known Dougherty Island 

 in latitude 59° S., alone offers even an unlikely possibility as a 

 breeding ground. 



The species /w,9ca is represented by the typical race which inhabits 

 the temperate southern Atlantic and Indian Oceans, over an area 

 having its longitudinal center in the neighborhood of the Cape of 

 Good Hope; and by a geographically separated race, campbelli, not 

 yet properly known to science, with a range in the Australian seas. 



Explanation of Plate. ' 



Fig. 1. Phoebetria palpebrata antarctica Mathews, adult cf and downy 

 nestling, Bay of Isles, South Georgia, Jan 20, 1913. Photo by R. C. 

 Murphy. 



Fig. 2. a, Phoebetria palpebrata auduboni Nichols and Murphy, No. 3903 

 Coll. of E. A. and O. Bangs, sex undetermined. Eastern Pacific Ocean. 

 b, Phoebetria fusca fusca Hilsenberg, No. 1952 cf, R- C. Murphy, 

 South Atlantic Ocean. 



