AVIFAUNA OF LAYSAN, ETC. 



289 



90. iESTRELATA PHjEOPYGIA SANDWICHENSIS, Ridgw. 



UUATL 



?? Procellaria alba (non Gmelin I), Bloxam in Byron's Voyage, p. 252 (1826) j Dole, Proc. Boston Soc. Nat. 



Hist. xii. p. 308 (1869); id. Hawaii. Alman. 1879, p. 55. 

 JEstrelata sandwichensis, Ridgway in Baird, Brewer, & Ridgw. Water-B. N. America, ii. p. 395 (1881) j id. 



Proc. U.S. Nat. Mus. ix. p. 95 (1886) ; id. op. cit. xi. p. 101 (1888) j id. op. cit. xix. p. 649 (1896) j 



Stejn. op. cit. x. p. 77 (1887). 

 (Estrelata phcBopygia, Wilson & Evans, Aves Hawaii, pt. v. (text) (1894), pt. vii. (plate) (1899) (lull 



synonymy); Salvin, Cat. B. Brit. Mus. xxv. p. 408 (partim, specimen el) (literature imperfect, neither 



the first description of M. sandwichensis nor Wilson & Evans' work quoted, M. sandwichensis united 



with jE. phaopygia). 



There is nothing to indicate which species of Petrel was meant by Bloxam and Dole 

 (I. c), hut possibly they had seen the present species. 



Eidgway {I. c.) was the first to describe the Hawaiian form. Salvin afterwards united it 

 with hte JEstrelata phaopt/gia (cf. Proc. U.S. Nat. Mus. xix. p. 648; Nov. Zool. vi. p. 198), 

 in which he was followed for a time by Ridgway (1887), while this same author afterwards 

 (1896) was very doubtful as to the identity of JE. sandwichensis and plmopygia. It is 

 certainly a mistake to unite these two forms unhesitatingly, as Salvia did, thus stopping 

 future researches about a question which he makes us believe to be finally settled. 

 Mr. Hartert and I have examined the skin from Kauai (collected by Knudsen) in the British 

 Museum, and, comparing it with a series of Galapagos skins, we find the following 

 differences :— In JE. sandwichensis the bill is a little slenderer, the culminicorn, measured m 



f 



Nasal tube of JE. phmpygia. Nasal tube of A. sandwichensis. 



a straight line from the end of the hard covering of the curved anterior half to the tip, 

 measures 07 in. ; there is no dark patch in front of the base of the axillaries ; the nasal 

 tubes are smaller and their covering is less horny ; the dimensions are generally smaller. 

 In JE. phecopygia the bill is a little larger and bulkier, the anterior culminicorn measures 

 about 0-75 to 0'8 in. ; there is always a large slate-coloured patch in front of the base of the 

 axillaries, and the latter are often mixed with slate-colour ; the nasal tubes are longer, and 



