LARIN.E. CATARACTES. 257 



313. CATARACTES RICHARDSONII. RICHARDSON'S PIRATE- 

 BIRD. 



Bill an inch and a third in length, greyish-black, tinged 

 with blue above ; tarsus an inch and two-thirds, feet black ; 

 middle tail-feathers three inches longer than the rest, broad, 

 tapering moderately until near the end, when they rapidly nar- 

 row to a fine point. Male in summer with the upper part of 

 the head blackish-brown ; the nape and upper sides of the neck 

 yellowish-white; all the upper parts blackish-brown, the quills 

 darker, the primaries with the shafts white ; anterior part of 

 the forehead, the cheeks, throat, and lower part of the body 

 white, the fore-neck tinged with brown, the lower wing- 

 coverts and tail-coverts dark greyish-brown. Female similar 

 to the male. Individuals of both sexes vary in the extent of 

 white on the neck and breast, some being brown all over. 

 Young with the bill light blue, dusky at the end ; tarsi and 

 basal part of the feet light blue, the rest black ; plumage 

 sooty-brown, lighter beneath; feathers of the upper parts 

 margined with whitish ; lower parts transversely undulated 

 with pale greyish-yellow. 



Male, 21, 42, 13, 1 T 4 ^, 1-&, 1 T S T , T V Female, 19, 40. 



This active and predatory bird leads a wandering life, sel- 

 dom remaning long in one place, unless during the breeding 

 season. Its flight is rapid, gliding, and steady, when it is 

 proceeding to a distance, but it turns, winds, sails, or shoots 

 along, with extreme dexterity on occasion, and is thus enabled 

 to harass Mews and Terns while fishing, and to force them 

 to drop or disgorge part of their food, which it catches on 

 wing. In autumn it is frequently seen in our estuaries, but 

 in summer betakes itself chiefly to the northern coasts and 

 islands, where it breeds, generally in societies. The nest is 

 like that of a gull, and placed on the ground, usually in. a 

 marshy place. The eggs are two or three, ovato-pyriform, 

 ovate, or oblong, olivaceous, or of various shades of brown, 

 spotted and patched with umber-brown, and purplish-grey, 

 their length averaging two inches and a quarter. 



Arctic Gull. Man-of-war Bird. Boatswain. Teaser. 

 Dung Bird. Dung Hunter. Dirty Allen. Scote- Allen. 

 Allen. Scull. Badock. 



Lestris Bichardsonii, Temm. Man. d'Ornith. iv. 499. Ca- 

 taractes Richardsonii, Richardson's Pirate-bird, MacGilli- 

 vray, Brit. Birds, v. 



R 



