456 BIRDS OF AUSTRALIA. 



black ; tarsus and basal half of the interdigital membrane 

 fleshy white ; remainder of the toes and interdigital mem- 

 brane black. 



Total length 13 inches ; bill 1 and 5 lines ; wing S^ ; tail 4 ; 

 tarsi 1^ ; middle toe and nail If. 



Sp. 633. ^STRELATA COOKI, G. B. Gray. 



Cook's Petrel. 



Procellaria velox, Sol. MSS. Banks's Icon, inedit., t. 16? 



cooki, G. R. Gray in Dieff. Trav. in New Zeal., vol. ii. p. 199. 



This bird frequents the seas between Australia and New 

 Zealand. Like the JE. leucoptera, it is very delicately formed, 

 and with that bird, the yE. mollis, and the other species 

 having flesh-coloured tarsi, forms a very natural division of 

 the ProcellaridsB or Petrels. 



The following is Mr. Gray's description and admeasure- 

 ments as given in the zoology of the voyage of the ' Erebus' 

 and ' Terror,' and which will be seen to differ somewhat from 

 the description and admeasurements of jE. leucoptera. 



" Grey above, with the apex of each feather narrowly mar- 

 gined, as well as their bases, white ; oblong spot below each 

 eye, wing-coverts, secondaries, and quills brownish black, with 

 the basal portion of the inner webs of the two last white ; the 

 front cheeks, under wing-coverts, and the whole of the under 

 part white ; bill black ; tarsi and knee brownish yellow ; feet 

 black, with the intermediate webs yellow. 



" Total length 12| inches; bill, length 1 inch 7 lines, 

 depth in middle 3 J lines ; wings 2J inches ; tarsi 1 inch 2 

 lines." 



