39. PUFFINUS SUBALARIS, Ridgway. 



(RIDGWAY'S SHEARWATER.) 



Puflinus tenebrosus (nee Pelz.), Townsend, Pr. U. S. Nat. Mus., XIII., p. 142 (1890) ; 



id., Bull. Mus. C. Z. Harv., XXVII., p. 126 (1895). 

 Puffinus subalaris, Ridgway, Pr. U. S. Nat. Mus., XIX., p. 650 (1897, ex Townsend 



MSS.). 

 Puffinus obscurus (nee Gm.), Salvin, P. Z. S., 1883, p. 431. 

 Puffinus dbscurus subalaris, Rothschild and Hartert, Nov. Zool., VI., p. 195 (1899). 



Minor: ala 7.25-7.6 poll.: cauda brevi, 2.65-3.05 poll., rotundata: subtus albus : 

 axillaribus, hypochondriis, et subcaudalibus albis, aut plus minusve fumoso-brunneis. 



The Hon. Walter Rothschild and Dr. Hartert consider this species to be a form of 

 P. dbscurus, differing in the following points : — The flanks, which are pure white in the 

 latter bird, are distinctly dusky in P. subalaris ; the under wing-coverts resemble those 

 of P. auduboni, and though without any defined band round the edge of the wing, there 

 is a considerable amount of dusky-brown mottling. The lores are dark above, ashy- 

 white below ; the ear-coverts are dusky, bordered with white on their lower margin ; 

 the line between the white and the dusky-brown usually more sharply defined than 

 in P. obscurus or in P. auduboni, but the dusky colour does not encroach on the white 

 sides of the chest (Nov. Zool., VI., p. 195). The most obvious difference between 

 P. subalaris and P. auduboni lies in the dusky clouding on the flanks, under wing-coverts 

 and axillaries, as well as in the dark under tail-coverts in the former species. The 

 above is a summary of the conclusions of the authors before mentioned, and 

 coincides with Mr. Ridgway' s description. 



I have examined several specimens of P. subalaris in the British Museum and the 

 Rothschild Collection, and find that it is a smaller bird than P. auricularis, with dusky- 

 brown axillaries, and is further distinguished by having no black freckling on the sides 

 of the throat, but it is undoubtedly alhed by reason of its dusky-brown under tail-coverts. 

 P. subalaris differs from P. obscurus, and also from P. gavia, P. persicus, P. assimilis, 

 etc., in its sooty-black under tail-coverts, and from P. auricular is principally in its 

 dusky-brown axillaries and under wing-coverts, though these characters are found to 

 be variable in a series. 



117 



