36. PUFFINUS OPISTHOMELAS, Coues. 



(BLACK- VENTED SHEARWATER.) 

 (Plate 30.) 



Puffinus opisthomelas, Coues, Pr. Acad. Philad., 1864, pp. 139, 144 ; Salvin, Cat. 



Birds Brit. Mus., XXV., p. 380 (1896) ; Anthony, Auk, XVII., p. 247 (1900) ; 



Godman, Biol. Centr.-Amer., Aves., III., p. 434, note (1904). 

 Puflinus gavia (nee Forst.), Ridgway, Pr. U. S. Nat. Mus., III., pp. 12, 230 (1880) ; 



id. in Baird, Brewer, and Ridgway, Water-Birds N. Amer., II., p. 389 (1884) ; 



A. O. U. Checklist, N. Amer. Birds, 2nd ed., p. 32 (1895). 



Cauda breviore, rotundata : subtus albus : axillaribus albis, fuhginoso-brunneo 

 terminatis, vel fuliginosis, basin versus albis : subcaudalibus et hypochondrhs imis 

 nigricantibus : gutturis et colli lateribus cinerascenti-brunneo marmoratis. 



It has not hitherto been remarked that P. opisthomelas bears a strong resemblance to 

 P. ydlcovanus of the Mediterranean, but this is undoubtedly the case. It differs from 

 the latter in its slightly larger size, blacker under tail-coverts, and in the greater 

 amount of brown mottling on the sides of the throat and neck, which sometimes extends 

 across the latter, while the axillaries are white, with dusky ends. The range of P- 

 opisthomelas being restricted to the Pacific coast of America, its evident affinity with a 

 European species is a fact of singular interest. 



The first recorded specimens were procured by the late John Xantus, off Cape 

 St. Lucas, in Lower California. They were described by the late Professor Elliot 

 Coues, but for some time the species was considered to be identical with P. gavia. The 

 latter, however, has white under tail-coverts, and P. opisthomelas is now recognised as 

 distinct. 



Mr. A. W. Anthony, who has done so much to acquaint us with the habits and 

 distribution of the Pacific Shearwaters, says (Auk, XVLL, p. 247, 1900) that P. 

 opisthomelas is the most abundant species of the genus in western North America, and 

 that it is plentiful off the coast of Central California during the summer months, being 

 found at all seasons of the year south of the Santa Barbara Islands. Of its northern 

 range he was not quite certain, but considered that he had seen the species off the 



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