132 BULLETIN 121, UNITED STATES NATIONAL. MUSEUM. 



breeding!: ground. The supposition surely seems to be supported by circum- 

 stantial evidence, and it \Y0uld be altogether plausible were it not that main- 

 land breeding sites are almost unknown among the Tubinares. If the petrels 

 do actually nest in the Chilean mountains, their individual burrows are prob- 

 ably scattered over wide areas, for thickly populated colonies would soon be 

 discovered and decimated by predaceous mammals. 



Nothing further is known about the distribution or habits of this 

 rare species, but I hope to see the Hornby petrel eventually restored 

 to the American list on positive evidence. Nothing whatever seems 

 to be known about its life history. 



DISTRIBUTION. 



Breeding range. — Unknown. 



Range. — Known only from the " northwest coast of America '' and 

 from the coasts of Peru and Chile, as indicated above. 



OCEANODROMA FURCATA (Gmelin). 

 FORKED-TAILED PETREL. 



HABITS. 



Among the Tubinares of the north Pacific Ocean this beautiful 

 little petrel is one of the most Avidely distributed and most uni- 

 versally common species. On our cruise from Dixon Entrance to 

 Unimak Pass some of these graceful little birds were almost con- 

 stantly in sight, circling about the ship and flitting lightly over 

 the waves in search of some tiny morsels of food. We also saw 

 them frequently about the Aleutian Islands, as far west as Attn 

 Island. 



Nesting. — They were undoubtedly breeding on many, if not all, of 

 the islands in the Aleutian chain, though we actuall}^ found only one 

 small breeding colony. During that eventful afternoon on Tanaga 

 Island, June 25, 1911, we wandered inland over a broad and marshy 

 alluvial plain and up the valley of a little brook into the hills. We 

 collected during that half day over 40 specimens of our new sub- 

 species of ptarmigan, found and photographed several of their nests 

 and spent some time hunting for nests of Aleutian sandpipers, and 

 Northern phalaropes, both of which were breeding there quite com- 

 monly. Consequently we had but little time to devote to the forked- 

 tailed petrels, desirable as they were; but, as we came to some steep 

 grassy hills, Mr. Eollo H. Beck wandered off and discovered a small 

 colony of this species. The hills were about a mile back from the 

 bay and the nests were in tj^pical petrel burrows in the soft soil of 

 the steep grassy slopes near the base of the hill. Several burrows 

 were dug out, but only one fresh egg was found, on which the 



