OCEANITIDJE FKEGETTA 463 



Oceanites melanogaster, Shelley, B. Afr. i, p. 166 (1896). 

 Cymodroma melanogaster, Salvin, Cat. B. M. xxv, p. 364 (1896). 

 Fregetta melanogaster, Reichenow, Voa. Afr. i, p. 36 (1900). 



Description. Adult. General colour sooty-black, darkest on the 

 head and primaries, the coverts somewhat paler ; upper tail- coverts, 

 flanks and sides of the abdomen and bases of the under tail-coverts 

 and rectrices white ; middle of the abdomen sooty. Iris dark 

 brown ; bill and legs, including the webs, black. 



Length 8-25; wing 6-10; tail 2-75; culmen -60; tarsus 1-5; 

 middle toe -95. The curious flattened phalanges and claws at once 

 distinguish this Petrel. 



Distribution. The Black-bellied Petrel ranges over the Southern 

 Ocean, wandering northwards to the Tropic of Cancer in the 

 Atlantic and to the Bay of Bengal in the Indian Ocean ; it is 

 specially abundant in the southern part of the Indian Ocean and 

 in the seas of Australia and New Zealand. 



Gould, who described this species, states that he met with 

 it first off Cape Agulhas, when on his way to Australia, and it has 

 been recorded by several naturalists from the seas in the neighbour- 

 hood of the Cape since. Lord Lindsay (now the Earl of Crawford) 

 obtained examples in 36 S., lat. 40 E. long., and in 32 S. lat., 

 52 E. long., and the Southern Cross Expedition in 42 S. lat., 

 20 E. long. 



Like other Petrels it breeds on the Islands of the Southern 

 Ocean ; there are eggs in the British Museum from Kerguelen and 

 the Falklands, while Mr. Layard's correspondent, Captain Armson, 

 brought him eggs from the Crozet Islands. 



781. Fregetta grallaria. White-bellied Petrel. 



Procellaria grallaria, Vie ill N. Diet. d'Hist. Nat. xxv, p. 418 (1817). 

 Thalassidroma leucogaster, Gould, B. Aus. vii, pi. 63 (1847) ; Layard, 



B. S. Afr. p. 358 (1867). 

 Oceanitis leucogaster, Sharpe, cd. La yard's B. S. Afr. p. 764 (1884) ; 



Swinburne, P. E. Phys. Soc. Edin. ix, p. 197 (1886). 

 Cymodroma grallaria, Salvin, Cot. B. .M xxv, p. 366 (1896); Parkin. 



Ibis, 1900, p. 675. 

 Oceanites grallarius, Shelley, B. Afr. i, p. 166 (1896). 



Description. Adult. General colour sooty-black, rather greyer 

 on the back, darkest on the tail and primaries ; upper tail-coverts, 

 concealed bases of the feathers of the chin, lower breast, abdomen, 



