454 BUFFEL-HEADED DUCK. 
afforded by the great Mississippi valley. A single specimen was 
«obtained by Dr..Stejneger in January 1883, on Bering Island, off 
Kamchatka, being the only instance yet recorded from the Asiatic 
side. This Duck migrates to California—where it is very abundant 
between October and April, Texas, Mexico, the West Indies, and 
occasionally to the Bermudas. 
A nest found by Mr. Lockhart on the Yukon River was in a 
poplar, about twenty feet from the ground, and on July 7th con- 
tained ro eggs ; their colour was of an ivory-white, with a faint tinge 
of green: measurements 2 by 1'°5 in. Mr. A. C. Stark describes a 
nest from which he shot the female on May 27th 1882, in West 
Minnesota, as being in a hole in an oak-tree, which was only a few 
inches deep, and partly filled with decayed wood, whereon lay 8 eggs 
nearly buried indown. Thestomach of the above bird was crammed 
with small red worms ; but snails, leeches, grasses and aquatic plants 
are also eaten, while on the sea-coast shrimps and molluscs are 
obtained by diving. From its fatness this species is generally known 
in North America by the name of “ Butter-ball”; and it is also 
called the “Spirit-Duck,” owing to the alacrity with which it dis- 
appears beneath the water. Its note isa mere croak, like that of 
the .Golden-eye, but more.feeble. It is very tolerant of cold, and 
has been seen on the Ohio when that river was thickly covered with 
floating ice. 
The adult male has the forehead metallic-green, witha dash of the 
same colour on the back of the neck, while the crown and throat: 
are iridescent purple ; from behind the eye to the nape extends a 
large triangular white patch which terminates in a sort of crest; 
below the purplish-green neck comes a narrow white collar which 
meets the white under parts; back, rump and inner secondaries, 
black; outer secondaries, speculum and coverts chiefly white, 
variegated with black; tail slate-grey; bill bluish; irides dark 
brown ; legs and feet yellowish-pink. Length 15 in.; wing 6°75 in. 
The female is smaller; her head and neck are ash-brown, with 
a white patch behind the eye; the upper parts are chiefly 
greyish-brown ; the white on the wing is less defined, and the under 
parts are tinged with brownish-grey on the sides. The young at first 
resemble the female. 
