2294 The Zoologist — September, 1870. 



advance of the eyes, to the side of the nape; there more or less con- 

 fluent with each other, and then dispersed as isolated white streaks 

 over the sides of the neck to the shoulders. In many specimens, 

 however, apparently quite adult, these white stripes are hardly, if at 

 all, apparent beyond the nape. Rest of head, including chin and 

 upper part of throat, sooty or fuscous blackish, sometimes with a 

 cinereous tint; this colour extending as far as the interscapular region, 

 from which point the upper parts are more decidedly plumbeous, only 

 the wings and tail being somewhat darker and more fuscous. Sides 

 under the wings plumbeous black quite to the flanks ; this colour also 

 extending forward in front of the wings and continuous with that of 

 the sides of the neck and head. Under surface of wings pure white, 

 except a little dusky clouding along the edge; bases of primaries and 

 the greater portion of their inner webs white, deepening very gradually 

 through a continuously deepening shade of brownish gray, into dusky 

 at the tips. Entire under parts (except the sides, as just described) 

 pure white. 



Length lO'SO to ll'OO ; extent 1800 to 1850 ; wing 550 ; tail 175 ; 

 tarsus rOO; middle toe and claw r25, outer 1*20, inner TOO; bill 

 along culmen "70, rictus 1*10; gonys "40; height at base '25 to "30, 

 width about the same. 



Younger. — Bill and feet as above ; (bill sometimes, however, wholly 

 blackish). Without a crest; no while feathers about head, or only 

 slight traces thereof. Face, including region just about the base of 

 the bill, both above and below, crown and sides of the head to the 

 level of the commissure, with nape and back of neck, plumbeous 

 dusky ; other upper parts, particularly the wings, the same, but most 

 of the back with a more decided tint of plumbeous. Under wing- 

 coverts and primaries as in the adult. Sides under the wings narrowly 

 fusco-plumbeous, the lengthened feathers over the flanks variegated 

 with white. Entire under parts otherwise white ; this colour 

 extending far around on the sides of the upper neck, nape and 

 occiput. 



Considerable variation in plumage as well as in size, and to a 

 degree, in shape of bill, is exhibited by the numerous specimens 

 examined. The differences in the bill are chiefly those of size, the 

 rdlative proportions of the various measurements being pretty 

 constantly preserved. The bill is ahva3S slenderer, and usually longer 

 than that of Antiquus, approaching in this respect the bills of the true 

 lirachyrhamphi. The size of the whole bird varies somewhat, but not 



