346 Bulletin Wisconsin Natm'al History Society. [Vol. 10 , Nos. 3-4. 
thousands each (we counted over 8oo before tiring and getting out 
of range ahorse). Without other proof it seems evident they were 
eating midges, undoubtedly gorging their stomachs with this fly 
as the only adequate food supply visible for such legions of mostly 
white-bellied tree swallows (7 achy cine t a bicolor (Vieill.)), one 
solitary bam swallow ( Chelidon crytlirogaster (Bodd)), and pos¬ 
sibly one bank swallow (Riparia riparia (L.)). Lot necessarily 
accompanying these, but apparently attracted at the same time, 
in the same way, was a kingfisher ( Ceryle alcyon (Linn.)) and 
several sandpipers undetermined. The midges had capital roosting 
vegetation in the great numbers of grapevines, draping the trees 
along the shore road. 
In the afternoon trip about Oshkosh, I repeated observations 
as to the work of the birds. There were some flocks of swallows 
and a few red-winged blackbirds passing northwards in the direc¬ 
tion of Neenah, still busily feeding on such midges as dared to fly 
during broad daylight. Later as dusk began to come on, the 
midges began to fly in greater numbers again,, SO' that I expected 
to see the flocks of birds discontinue their northward movement, 
especially in the season of the year when such bird flocks are sup¬ 
posed to be migrating southwards. They, however, continued 
northward, still feeding. So remarkable a northward movement of 
birds over a considerable local area must be correlated with the 
swarming of plumosus. Although so correlating a northward 
movement for a half dozen bird species seen in one day, I am not 
unaware that ornithologists have interpreted short northward 
migrations of certain birds as practise flights previous to their 
main southward migration,—thus the snowy heron formerly. 
Other Enemies. —Miall & Hammond (1900, pp. 4-7) speak of 
a long list of aquatic creatures besides the vertebrates mentioned 
in the first pages and bibliography of this paper, to say nothing 
of birds other than those recorded in the present account, which 
prey upon Chironomids in different stages from the larval to the 
imaginal (sparrows, Judd, 1901, pp. 9, 32, 52, 65, 84). Mrs. Treat 
(1876, p. 386) notes that even aquatic plants feed on the larvae: 
“Upon two occasions I have found a dead Chironomus larva held 
fast in the valve, and while I was looking, the valve suddenly 
opened and ingulfed the larva with sufficient force to send it to 
