PEIOOELLA. — DIOMEDEA. 437 



ffab. Mexico, Mazatlan ^. — Seas of the Southern Hemisphere ^, northward along the 

 Pacific Coast of North America to Washington Territory ^ ^. 



This Petrel is easily recognized by its large size and silvery-grey plumage, resembling 

 that of the Northern Fulmar (Fulmarus gracilis). 



The species is found in the Cape seas and also in the Antarctic pack-ice, where 

 Hanson procured several specimens which were swimming about in search of food. It 

 is believed to breed in Kerguelen, but the eggs have not yet been obtained. 



Fam. DIOMEDEID^. 



The characters for the determination of the Albatrosses as distinct from other Petrels 

 are thus given by Salvin in the ' Catalogue of Birds ' : — Nostrils lateral, separated by the 

 wide culmen, each in a separate horny sheath opening forwards ; margin of the sternum 

 uneven, the sternum itself short compared with its width ; no pterygoid processes ; 

 manubrium of furcula very short ; coracoids short, very wide at the base and widely 

 divergent ; first primary the longest. 



The Albatrosses are distributed over the entire Southern Hemisphere, retiring to 

 rocky islands to nest. In the Pacific they extend as far north as Japan and the 

 Hawaiian Islands. Only three genera are known — Diomedea, Thalassogeron, and 

 Phcehetria, and a single species of two of them has occurred within our limits. 



DIOMEDEA. 



Biomedea, Linn. Syst. Nat. L p. 214 (1766); Salvin, Cat. Birds Brit. Mus. xxv. p. 440 (1896). 



The typical Albatrosses have no such groove along the sides of the culmen as is found 

 in the Sooty Albatross {Phoeletria fuUginosa), and the tail is short and rounded. The 

 bill is, as it were, divided into sections or horny layers, and thus in Biomedea the 

 base of the " culminicorn," or upper sheath, is wide, joining the proximal end of the 

 dorsal edge of the " latericorn," or lateral plate of the culmen. 



The species are nine in number, and are principally inhabitants of the Southern 

 Hemisphere, though they are seen occasionally north of the Equator. Two species, 

 B. nigrijpes and I), albatrus, are inhabitants of the Northern Pacific, and the former 

 has been noticed near the Eevillagigedo Islands. 



1. Diomedea nigripes. 



Diomedea nignpes,^ Auinhon, Orn. Biogr. v. p. 327'; Salv. Cat. Birds Brit. Mus. xxv. p. 445 '; 

 Anthony, Auk, xv. p. 317' ; Gates, Cat. Eggs Brit. Mus. i. p. 163 \ 



Fuliginoso-brunnea, facie lateral! et corpore subtus toto paUidioribus, magis cinerascentibus ; pileo albicanti- 

 brunneo variegato, plumis pallidius marginatls ; regione anteoculari nigricante ; f ronte basali, loris, et genia 

 anticis cinerascenti-albis, mento clariore cinereo ; subalaribus et axiUaribus saturate brunneis : rostro 



