130 PATAGONIAN EXPEDITIONS: ZOOLOGY. 



Neck : Nape and upper neck smoky brown with a marked greyish tinge 

 and much lighter (approaching white) in shade than the crown and occi- 

 put. Below and on sides white. 



Back : Greyish smoky brown, each feather broadly margined with a 

 lighter shade, often approaching white. Longest upper tail coverts mostly 

 white. 



Wing : The greater coverts like back ; the shoulders darker, but sim- 

 ilarly margined with lighter shade. Primary quills dark umber brown on 

 their exposed surfaces, becoming white on the under webs, both webs and 

 the shafts white at their bases. 



Tail : Dark umber brown, the central rectrices nearly an inch longer 

 than the outer ones. The intermediate feathers graded to form a rounded 

 tail when spread. 



Lower parts white, except on the middle of the abdomen, where the 

 white is more or less obscured by smoky grey. Flanks smoky grey with 

 lighter edging to the feathers. Lower tail coverts smoky grey with 

 mottling and broad tipping of whitish. Some of the feathers on the 

 sides under the wings are mottled with dark greyish smoke color. 



Bill : Dark brown color, paler on the lower mandible. 



Tarsus : Outer surface dark umber brown, inner surface yellowish flesh 

 color. 



Feet and webs pale yellowish flesh color darkest above, lightest below. 

 The exterior toe umber brown like the outer surface of the tarsus. 



Iris : Dark hazel brown. 



The female is similar to the male in color but averages a little smaller 

 in size. 



Geographical Range. — Atlantic Ocean. From the Faroe Islands and 

 Greenland on the north, to the Cape of Good Hope, the Falkland Islands 

 and Cape Horn. 



There appear to be no definite records of the breeding range of P. gravis. 



This bird was not obtained or observed by the Princeton Expeditions 

 to Patagonia. The description is based on an apparently adult male, 

 cited above, compared with twenty six (26) other individuals all taken 

 about twenty miles off the coast of Cape Cod, Massachusetts, nos. 8577 

 to 8602 P. U. O. Coll. August 1 88 1 (William E. D. Scott, collector). 



