172 ALLEN'S NATURALIST'S LIBRARY. 



the anterior edge. The tail is moderate and rounded. The 

 bill is rather short, stout, and black ; the nasal opening is 

 slightly directed upwards ; the claw of the hallux small. (Cf. 

 Salvin, Cat. B. Brit. Mus. xxv. p. 368). 



I. THE CAPPED PETREL. CESTRELATA HdLSITATA. 



Procellaria h&sitata, Kuril, Beitr. p. 142 (1820). 



(Estrelata hcesitata, Dresser. B. Eur. viii. p. 545, pi. 618 



(1880); B. O. U. List Brit. B. p. 200 (1883); Saunders, 



ed. Yarrell's Brit. B. iv. p. 8 (1884) ; id. Man. Brit. B. 



p. 713 (1889); Salvin, Cat. B. Brit. Mus. xxv. p. 402 



(1896). 



Adult. General colour above sooty-brown, with obsolete 

 margins of lighter brown on the feathers of the back ; the 

 lower back and rump slightly blacker, as also the wing-coverts 

 and scapulars; upper tail-coverts white; tail slightly wedge- 

 shaped, black, with a good deal of white towards the base ; 

 crown of head blackish, forming a cap; hind-neck white, with 

 a few sooty-brown bars on the nape; lores white; feathers 

 below the eye sooty-brown ; sides of face, ear-coverts, and 

 under surface of body, white, with a little sooty-brown on the 

 upper sides of the breast ; a few of the lower flanks tipped 

 with sooty-brown ; under wing-coverts and axillaries white, the 

 lesser and marginal coverts blackish, forming a broad border to 

 the inner aspect of the wing; lower primary-coverts white, 

 tipped with black spots ; quill-lining ashy ; bill black ; tarsi 

 and toes yellow, the distal portion of the latter, and the webs 

 for the same distance, black. Total length, 16*0 inches ; 

 culmen, 17; wing, 11*3; tail, 3*8; centre feathers, 5-0; 

 tarsus, i '56. 



Characters. The distinguishing characters of this species 

 are given by Mr. Salvin as follows : " The exposed portion of 

 the outer primary beneath is dark, not white ; the bill is wide 

 at the gape ; the under surface is white, as well as the back of 

 the neck ; the crown is blackish, and the upper tail-coverts are 

 white. (Cf. Salvin, Cat. B. Brit. Mus. xxv. p. 398.) 



Range in Great Britain. The only instance of the occurrence 

 gf this rare Petrel in Great Britain is that of a specimen taken 



