THE WHITE- HEADED PETREL 



57 



The Great-winged Petrel. 



CEstrelata macroptera. 



Southern oceans. 



Dark aooty-browu, under surface paler, forehead and throat greyer. 

 Total length about 16.5 inches, wing 12 to 13, tall central 4.5, lateral 4, 

 bill 1.7, tarsus 1.65. 



Nest a burrow about three feet in length, with larger chamber 

 at end than usual ; the single white egg measures 2.6 x 1.91 inch. 



Great-winged Petrel: Oestrelata macroptera. 



After Smith. 



The White-headed Petrel. 



(Estrelata lessoni. 



South Indian Ocean, Australian and New Zealand seas. 



Upper surface grey, lighter towards the crown, which is nearly 

 white; feathers of back edged with paler grey; sides of neck mottled 

 with bars of grey and white; wings nearly black, tail grey; forehead and 

 under surface white; just below and in front of the eye black. Total 

 length about 18 inches, wing 12.2, tail, central 5, lateral 3.7, bill 1.9, 

 tarsus 1.8. 



Nest rather a short tunnel with a large chamber at the end. 

 The single egg is white, and measures about 2.78 x 1.88 inch. 



