144 PATAGONIAN EXPEDITIONS: ZOOLOGY. 



"The white spots on the throat and cheeks appear to vary much with 

 age. In the perfectly adult bird the triangular gular spot is alone left ; 

 that on the cheeks, which is connected with it in immature birds, having 

 disappeared. Very young birds have the under parts almost wholly 

 whitish, which afterward deepen into fuliginosus." (Coues, Proc. Acad. 

 Sci. Philad. 1864, p. 118.) 



Geographical Range. — Southern Oceans, north to about latitude 30° 

 south. 



This petrel was not obtained by the Princeton Expeditions to Pata- 

 gonia. The material examined to form a basis for the description given 

 is in the Collection of the Academy of Natural Sciences of Philadelphia, 

 and a large series in the British Museum of Natural History. 



The birds have been collected and observed in the Straits of Magellan 

 and at points off the Patagonian Coast. 



The Great Black Petrel breeds in numbers at Kerguelen Island in 

 December, and the following observations of its habits at that season are 

 of interest : 



"Nests in very deep burrows in hill-sides, generally under a mound 

 of herbage. Near the entrance to the burrow, there is always, so far as 

 observed, a small pool of fresh water. Egg is single, regularly ovoid, 

 and white, without shell-markings of any kind. It is generally, however, 

 much soiled by secretions from the oviduct and dirt from the burrow. 

 The shell is thin, homogeneous, and compact in structure, very smooth to 

 the touch, but under the lens is seen to be marked by small pits and 

 shallow linear depressions." (Natural History of Kerguelen Island, J. H. 

 Kidder, M. D., Bull. no. 3, U. S. Nat. Mus. p. 13, 1876.) 



Genus PAGODROMA Bonaparte. 



Type. 

 Pagodronia, Bonap. Consp. Av. ii. p. 192 (1855); Coues, Proc. 

 Acad. Sci. Philad. 1866, p. 159; Salvin, Cat. Bds. Brit. Mus. 

 XXV. p. 419 (1896); Sharpe, Hand-List Bds. I. p. 127 

 (1899) P. nivea. 



GeograpJiical Range. — Antarctic Seas. 



