496 Count E. Arrigoni Degli Oddi on 



with buff; the back witli a brownish appearance, but the 

 end of the feathers huffish ; the wings and lower back hke 

 those of the Yellow-legged Herring-Gull, but the edges 

 broader, and the huffish tint lighter and not overspread 

 with grey, but with whitish yellow ; chin and throat huffish 

 white ; undcr-parts greyish, with the feathers edged with 

 buffi-h, the grey tint overspread with brownish, more distinct 

 on the sides of the breast and of the upper abdomen ; lower 

 abdomen, vent, under tail-eoverts, and the sides snow-white, 

 some of the lateral under tail-coverts shewing a dark greyish 

 spot tow^ards the end of the feathers on the outer web ; tail- 

 feathers blackish, with a broad terminal band and an edge 

 of light huffish white, the base of a delicate pearly white, 

 the light pattern more extended on the inner webs of the 

 outside feathers ; feet dark dirty plumbeous. 



Bill from forehead 1'67 inch ; wing 13 5 inches. 



A young male of the same age, date, and locality has 

 the greyish on the head and upper- parts darker, and also 

 the dark tint on the under-parts, so that the contrast with 

 the snow-white of the belly is more evident. 



Bill from forehead 1"6 inch ; wing 12*4 inches. 



Two other females from the same locality and with the 

 same date are younger and not fully grown; they resemble 

 the above-mentioned young males, but there are some grey 

 downy tracts on the neck and on the sides of the head. 



Bill from forehead 1*6 inch; wing 10*7 inches. 



Besides the small size and the dimensions of the bill and 

 wing, the differently coloured bill, the darker and more 

 uniform pattern of the plumage, the snow-white abdomen 

 and vent, we must call attention to the very different pattern 

 of the tail-feathers and the shape of the bill, which enable us 

 to recognise this species at once in its first dress after the 

 downy nestling-period. 



Yellow-legged Herring -Gull, young, in the first dress. 

 Bill stouter and larger, with the rami of the lower mandible 

 straight or a little arched, the space from the gonys to the 



