NATATORES. ALCADAs. 417 
Fore part of the neck having a large patch of deep 
orange-brown. Lower part of the neck, and sides of 
the breast, white, with the central parts of the feathers 
blackish-grey. 
Under plumage silvery white, except the flanks, which are 
deep clove-brown. Upper plumage deep clove-brown, 
with a slight glossy green reflection. Ivrides red. Out- 
side of the legs greenish-grey ; inside livid, or purplish- 
white, tinged with blue. Membrane of the toes the 
same. 
Puate 78. represents a Young Bird, of the natural size. | Young 
Forehead, crown, nape, and back part of the neck deep ee 
grey, finely streaked with greyish-white. Chin, throat, 
and under plumage, white. Flanks with large arrow- 
shaped dark grey spots. Upper plumage blackish-grey, 
inclining to clove-brown ; the margins of the feathers 
being deeply bordered near their tips with white and 
smoke-grey. Quills deep clove-brown. Bill ash-grey, 
tinged with flesh-red. Outsides of the legs dark green- 
ish-grey : inside surface and webs greenish-white. Irides 
reddish-brown. 
After the second moult, the grey upon the head, cheeks, 
&e. acquires the tint of the adult; and a few red fea- 
thers are often found mixed with the white upon the 
fore part of the neck. The upper parts assume a deeper 
tint ; the spots of white grow less, frequently changing 
to a yellowish-white ; and as the bird advances to ma- 
turity entirely disappear. 
FAMILY IIIl.—ALCAD. 
ApproacHine closely in form, and possessing natatorial 
powers fully equal to the Colymbide, the present family, 
vol I. pd 
