AVES DIOMEDEID^. 167 



Color. Adttlt Male. — General color, white, with transverse dark lines 

 on upper back and dark wings. 



Head white. 



Neck white. 



Back from base of neck banded with narrow transverse wavy lines of 

 dusky brown. Lower back white. 



Wings : The scapulars are more strongly banded than the back, but 

 the banding becomes indefinite and the general direction of the lines more 

 parallel with the margins of the feathers. In the longest scapulars these 

 lines merge into one another forming a slaty black tip to the feathers. 



The wing proper is slaty black, the lesser coverts having a varying 

 amount of white on their inner webs, increasing toward the edge of the 

 wing. 



The middle and greater coverts are narrowly edged with white. 



The primaries are black on their exposed surfaces, the concealed por- 

 tion of the shafts being yellowish white, and of the webs nearly pure white. 



Tail : White. Most birds show some traces of dark markings on the 

 webs of the rectrices. 



Under parts white. 



Bill yellowish horn color, orange at the base. 



Legs flesh color. 



Feet flesh color. 



Immature birds, are dark brown above, palest on the neck and with a 

 dark patch on the crown. The forehead, sides of the head and throat are 

 white. The under surface is yellowish or brownish white, palest on the 

 belly. The flanks are mottled with dusky, and the under tail coverts are 

 dusky brown. 



Geographical Range. — Southern Oceans. Seas about the Cape of 

 Good Hope and Cape Horn. South Atlantic and South Pacific Oceans 

 regularly north to about 30° south latitude. Casually in the Atlantic to 

 the coast of Florida, and in the Pacific to the coast of Washington. 



The description is based on material in the British Museum of Natural 

 History. 



The following biographical notes on the species may be quoted : 



