286 Trans. Acad. Sci. of St. Lows. 
use common roosts in the bottoms, scattering over the entire 
county at early dawn to feed. The southward movement com- 
mences early in October and continues until well into December. 
AGELAIUS PHOENICEUS ForTIS Ridgway. Thick-billed Red-wing. 
Irregular, sometimes very abundant, migrant and winter resident. 
DISTRIBUTION OF A. P. FORTIS 
ine 
% cs. 
. 
SENN 
Ls 
f ‘ 
array dia] UG 
\ 
‘ 
5S 
Scoetes 
z 
= 
= 
1 
e 
= om 2 
ai 
! 
| 
' 
= 
m 
x 
D 
a 
Continuous line encloses breeding range. 
Broken line shows extent of winter range. 
The Red-wings wintering in this vicinity were long suspected 
of belonging to this very noticeably larger subspecies, but prior 
to the winter of 1916-1917 no systematic investigation had ever 
been made in western Missouri to establish their subspecifie status. 
This rather severe winter proved to be a favorable one for this 
study, as the birds were present in unusual abundance. A large 
series of specimens was taken over a wide area and covering the 
entire period of their sojourn. 
They began arriving in small numbers during the middle of 
November and continued coming in increasing numbers until 
during the intense cold periods of late December and January 
there were countless thousands resorting to common roosts in 
the timbered bottoms along the Missouri River. In the early 
mornings when the birds scattered to feed, great flocks flew over 
