BIRDS OF MINNESOTA. 59 
Mr. Washburn states that they are reputedly regular summer 
residents, and breed near Fergus Falls in rather limited num- 
bers. He regarded them as a moderately represented species 
in the breeding season, the larger proportion going further 
north. In each of my personal explorations in Wright, Meeker, 
and Kandiyohi counties, I have carefully sought for informa- 
tion respecting the nidifying habits of this species in those 
sections, and have been so far rewarded as to find their eggs in 
the possession of several persons residing there, and obtain 
such detailed descriptions as to the location of the nests, and 
general habits of the Blue-bills as leaves no doubt of their 
breeding there, though nowhere numerously. I was shown 
the deserted nest in one instance, but their well known resem- 
blance to those of the Mallards in both location and structure, 
robbed the observation of all value in the absence of the eggs 
and the duck. In every shooting season the variation of the 
measures of the Blue-bills has arrested the attention of sports- 
men as well as naturalists, yet very few have overlooked their 
persistent habits enough to confound them with the Little 
Black-heads (A. affinis). Under my notes of measurements for 
thirty years the variations in this species have never exceeded 
20.75 inches in length; wing, 9.25; nor fallen below 17.50 and 
8, while the Little Black-heads have been between 17.50 in 
length; with the wing, 8; and 15, in length, with the wing, 
7.25. Ihave never doubted the specific distinction of these 
two ducks since I became more familiar with their habits, 
although inclined to do so before; but I cannot account for 
intermediate forms, or rather intergrading measurements, by 
any proportionate hybridism, as has been so stoutly obtained. 
Although they are here so assuredly during the entire season, 
their habits do not make them specially observed to any marked 
extent, until they begin to gather into appreciable flocks late 
in the autumn; often into November, after which they remain 
but a short time. 
SPECIFIC CHARACTERS. 
Head and neck all around, jugulum and shoulders, lower part 
of back, tail, and coverts, black; head with a gloss of dark 
green on sides; rest of under parts white; feathers on lower 
parts of belly and side, the long feathers of the flanks, inter. 
scapular and scapulars white, waved in zigzag transversely 
with black; greater and middle wing coverts similarly marked 
but more finely and obscurely; greater coverts towards the 
tips and the tertials greenish black; speculum white, bordered 
behind by greenish black; white extending across the whole of 
