OCEANODEOMA CEYPTOLEUCTJEA. 



(RIDGWAY'S PETREL.) 



Thalassidroma , Dole, Proc. Bost. Soc. Nat. Hist. sii. p. 308, Extr. p. 15 (1869). 



Procellaria, sp.], Melliss, Ibis, 1870, p. 105. 



Cymochorea eryptoleucura, Ridgw. Proc. U. S. Nat. Mus. iv. p. 337 (1882). 



Oceanodroma eryptoleucura (Ridgw.), Stejn. Proc. U. S. Nat. Mus. ix. p. 78 (1887). 



Figura unica. 

 Wilson, Aves Hawaiienses, part iv. 



Ad. nigricanti-fuscus, vis schistaceo tinctus : remigibus nigricantibus, secundariis intimis tectricibusque 

 alarum grisescenti-fuscis, apicem versus griseo-albidis : supracaudalibus nigris, conspicue nigro termi- 

 natis : cauda inconspicue furcata, rectricibus (medianis exceptis) ad basin albis : rostro et pedibus 

 nigris : iride fusca. 



Pull, ubique lanugine indutus, saturate schistaceo-fuliginosus. 



Adult Male (Porto Santo, June 12th). Resembles Leach's Petrel, but is rather browner in tone of colour ; 

 tail less deeply forked, white at the base for about one quarter of its length, except the middle 

 rectrices, which are black ; upper tail-coverts white, broadly tipped with black. Total length about 

 7 inches, cuimen 085, wing 6'0, tail 2 - 8, the central rectrices 0'2 shorter than the outer ones, 

 tarsus 085. 



Adidt Female (Ukeo-chao, June 20th). Resembles the male. Cuimen 0'85 inch, wing 6"1, tail 3 - 0, the 

 central rectrices 022 shorter than the lateral ones, tarsus 09. 



Nestling (Desertas, September 20th). The wing and tail-feathers are well grown and similar to those of 

 the adult, but shorter; the white bases of the lateral tail-feathers are very fully developed ; rest of the 

 body covered with slaty blackish down. 



The present species was first described in 1882 by Mr. Ridgway from specimens obtained in 

 Hawaii by Mr. Knudsen, and Mr. Scott Wilson received specimens procured by Mr. Francis Gay 

 on tbe island of Niihau. It has also, according to Mr. Salvin, been obtained on the Galapagos 

 Islands. Quite recently it has been found to inhabit the Atlantic as far south as St. Helena, 

 whence there are specimens in tbe British Museum ; and it has strayed, at least on one occasion, 

 as far as England, a specimen in the collection of Mr. Boyd Alexander having been picked 

 up dead on the beach at Littlestone, in Kent, on tbe 5th of December, 1895. It is very possible 

 that it may have occurred oftener on our shores and have been mistaken for 0. leucorrhoa ; and 

 it would be well if those collectors who possess specimens, determined as being Fork-tailed 

 Petrels from the coasts of Great Britain, were to carefully examine these birds and make sure 

 that they are Fork-tailed Petrels and not 0. eryptoleucura. 



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