247 
the first week in January, in 1884, drove it southward from all but the 
most favorable localities. About twenty birds remained through Jan- 
uary at Saint Louis, and not quite so many at Manhattan, Kans. It 
was not until the middle of March that the northward movement com- 
menced. This was marked at Caddo, Ind. Ter., by the return of the 
birds from the bottom lands, whither they had been driven by the cold, 
to the edges of the prairie. There was scarcely any increase in numbers 
until April 1. At more northern localities the first wave was marked 
by the arrival of more birds. This wave reached latitude 39° the 
last week of March, but was stopped by the heavy snow-storms of the 
first week in April and made no further advance until the middle of 
the month. Out of the nineteen records of arrival at stations between 
latitude 39° and latitude 45° but two mentioned any Ycllow-rumps. «: 
before April 16. But on that and the two following days they appeared 
in large numbers over the whole of these 200,000 square miles. What 
an incredible number of Yellow-rumps must have been moving on those 
three days! The same wave brought the bulk to the region south of 
latitude 39°, and another two weeks carried it up to latitude 45°, mak- 
ing the species, for the time being, one of the most numerous birds of 
the Upper Mississippi Valley. Having now passed over the land of 
spring-time and reached a country still ruled by winter, they checked 
the hurriedness of their flight and did not reach Portage La Prairie, 
Manitoba, until the first week in May. A few breed in northern Min- 
nesota, but the bulk pass on to breed in British America. A curious 
incident occurred in the migration of this species at Heron Lake, in 
southwestern Minnesota. On March 18 there arrived an immense flight 
of Ducks, all coming from the west as if from the Missouri Valley. 
Together with them, or at least on the same day, came great flocks of 
Blackbirds and “a large flight of Yellow-rumps in fine feather and 
song.” Where they came from is a mystery. A competent observer 
on the Missouri River southwest of Heron Lake did not find the species 
common until nearly two months later, and no station south or south- 
east reported them at all until three weeks later, nor at Heron Lake 
was the arrival of the bulk noted until thirty-three days afterwards. 
It would seem to be a case of a flock caught up by some upper-air cur- 
rent and carried farther than they intended. While most of the birds 
left central Illinois the first week in May, some very late migrants were 
seen at Whitehall May 21. 
In the fall of 1884 the first note of the Yellow-rumped Warbler came 
from the edge of its breeding-grounds at Elk River, Minn., where the 
bulk arrived September 9; the bulk left October 8, and the last Novem- 
ber 5. The first was noted from Des Moines, Iowa, October 18; the 
bulk October 21, and the last October 25. At Mount Carmel, Mo., the 
first was reported September 27; departure of bulk October 22, and 
last seen November 3. During the winter of 1884~85 no reports were 
received of irregular wintering of the Yellow-rumps, except from Man.- 
