1878.] COLLECTED BY H. M.S. 'CHALLENGER.' 739 



pedition, five are males and three females. They thus offer an 

 opportunity of testing the view advanced by Mr. Sharpe as to the 

 supposed sexual difference in the size of the bill existing in these 

 birds 1 . 



In these specimens there is no tangible difference between the bills 

 of the sexes ; and as the opposite sexes of P. banksi, as shown by the 

 two * Challenger ' specimens, are also alike as regards the size of the 

 bills, doubts may fairly be raised whether the great difference obser- 

 vable in the size of the bills in these birds is a sexual character at all. 



Prion banksi. 



Pachyptila banksi, Smith, 111. Z. S. Afr. Birds, pi. 55. 

 Pseudo-priori banksi, Coues, Pr. Ac. Phil. 1866, p. 166. 



a. Male. Marion Island. 

 "Eyes brown." 



b. Female. " Caught at sea near Crozets." 



Without attempting to decide the question as to how many species 

 of Prion exist, I use the name P. banksi for these birds, as then- 

 bills agree most nearly with that of the type of P. banksi in the 

 British Museum. 



Pelecanoides urinatrix. 



Procellaria urinatrix, Gm. Syst. Nat. i. p. 560. 

 Pelecanoides urinatrix, Coues, Pr. Ac. Phil. 1866, p. 190; Sharpe, 

 Zool. Kerg., Birds, p. 14. 



a. Male. Kerguelen. 

 " Eyes dark grey." 



b. Male. Betsy Cove, Kerguelen. Obtained January 1874. 



c. Male. Christmas Harbour, Kerguelen. 



d. Male. Betsy Cove, Kerguelen. 

 e-h. Females. Kerguelen. 



i. Kerguelen. 



/. Young. Kerguelen ? 



Pelecanoides garnoti. 



Puffinuria garnoti, Less. Voy. Coq. Zool. pi. 46. 

 Pelecanoides garnoti, Coues, Pr. Ac. Phil. 1866, p. 190. 



640* Male ? ' f ^ 0ve Harbour, Messier Channel. 



" Eyes hazel. These birds and another one which was put in spirit 

 were found dead. Two were picked up by the boat in which Cap- 

 tain Maclear and I went, floating on the surface of the water ; and 

 the third was picked up by the galley on the rocks. They were quite 

 fresh ; the bodies were very thin. 



" Their stomachs were filled with small leaves. It looks very much 



1 Latham seems to have been the first author who mentioned this supposed 



sexual difference in Prion. After describing P. vittatus (Syn. iii. p. 414), he adds : 



" The female has the same plumage ; but the bill, though greatly exceeding that 

 of any other Petrel, is scarcely more than half the breadth of that of the " male." 



