448 LARIU.E. 



white ; legs ratlior short, and dusky in colour, the toes and 

 intcrdigital membranes also ; the hind toe only a small 

 tubercle without any projecting horny nail or claw, and on 

 this account the species was called tridactylus, three toed. 



The whole length fifteen inches and a half; from the 

 anterior joint of the wing to the end of the longest quill- 

 feather twelve inches. 



The adult bird in winter has the lower part of the neck 

 behind French grey, like the back ; the occiput, top of the 

 head and the region of the ear-coverts streaked with dusky 

 grey, the other parts as in summer. 



Young birds of the year have the bill black ; the irides 

 dusky, almost black ; upper part of the head white ; the 

 occiput and nape with a few dusky grey patches on a white 

 ground ; the lower part of the neck behind marked by nu- 

 merous blackish-grey feathers, forming transverse crescentic 

 bands ; back, scapulars, great wing-coverts, and secondaries 

 French grey ; point of the wing, and the series of smaller 

 wing-coverts nearly black, forming a conspicuous dark stripe 

 down the wing when closed, and across it when expanded; 

 tertials French grey, with a spot of black near the end, the 

 inner broad web varied with white ; tail-coverts and tail- 

 feathers white, the latter black at the end, forming a con- 

 spicuous transverse bar ; the middle tail-feathers having the 

 largest portion of black, the outer tail-feather on each side 

 the smallest ; chin, neck, breast, and all the under surface of 

 the body pure white ; imdcr tail-coverts white, tail-feathers 

 white at the base, ending in dark or lead-grey ; legs, toes, 

 and membranes pale brown. 



