454 BIRDS OF AUSTRALIA. 



Its powers of flight are considerable, and the action of its 

 wings is very rapid. 



The food, which appears to be precisely the same as that of 

 the other Petrels, consists of mollusks, the fat of dead cetacea, 

 small fish, &c. 



The sexes are similar in colour, but the young differ from 

 the adult in having all the under surface dark grey and the 

 throat speckled with grey. 



Crown of the head and all the upper surface slate-grey, the 

 feathers of the forehead margined with white ; wings dark 

 brown ; before and beneath the eye a mark of brownish black; 

 face, throat, and all the under surface pure white, interrupted 

 by the slate-grey of the upper surface advancing upon the 

 sides of the chest and forming a faint band across the breast ; 

 centre tail-feathers dark grey ; outer feathers greyish white, 

 freckled with dark grey ; bill black ; tarsi, base of the toes 

 and basal half of the interdigital membrane pale fleshy white, 

 the remainder black. 



Total length 13 J inches ; bill IJ ; wing 9f ; tail 5 ; tarsi If ; 

 middle toe and nail If. 



Sp. 632. iESTRELATA LEUCOPTERA, Gotcld. 



White-winged Petrel. 



Procellaria leucoptera, Gould in Proc. of Zool. Soc, part xii. p. 57. 

 Rhantistes leucoptera, Bonap. Compt. Rend, de FAcad. Sci., 1856. 

 Cookilaria leucoptera, Bonap. Consp. Gen. Av., torn. ii. p. 190, Cooki- 



laria, sp. 1. 

 Procellaria velox, Sol. MSS. ? 



Procellaria cookii, Gould, Birds of Australia, fol., vol. vii. pi. 51. 



I feel assm'cd that this bird is diff'erent from the P. cooki 

 of Mr. G. R. Gray. On comparing the specimens of both, 

 now before me, I find that my bird, which was obtained 

 while breeding on Cabbage Tree Island at the mouth of Port 

 Stephen's Harbour, has a shorter and much stouter bill, a 



