Harris—Birds of the Kansas City Region. 287 
the city to their feeding grounds on the prairie regions many 
miles to the south and west. It is estimated that some of the 
flocks covered daily from thirty to fifty miles on these journeys. 
As early as the middle of February much singing and mating 
activity was noted among the flocks and the ranks were begin- 
ning to thin. On March 2nd the last specimens of fortis were 
taken (from large masses of birds), and by March 5th this form 
had been almost entirely replaced by equally large flocks of 
predatorius. Several specimens taken on this date from large 
flocks proved to be referable to the breeding form. A difference 
was also noted in the music of the flocks, as the notes of fortis 
are softer, more melodious and less grating than those of pred- 
atorws. 
These northwestern birds do not seem to have passed down 
the Missouri Valley (east) beyond this point, as only an occa- 
sional bird was seen in the nearby down-river counties. 
The stomachs of ten males and one female taken from one 
flock on January 17th contained large quantities of the seeds of 
sorghum (Sorghum sp.) and knotweed (Polygonum lapathifo- 
lium L.). 
Very few Northern Red-wings (A. p. arctolegus) were pres- 
ent during this hard winter, though during the equally severe 
winter of 1917-1918 this form greatly predominated. 
AGELAIUS PHOENICEUS ARCTOLEGUS Oberholser. Northern Red- 
wing. 
Abundant migrant; irregular, sometimes very common winter resi- 
dent. 
Large moving masses of this recently described subspecies are 
not readily distinguishable in the field from the Thick-bill, and 
may even be mistaken for the breeding form unless seen at close 
range or in mixed flocks. Not enough material has yet been 
secured to give, with certainty the dates of its arrival from the 
north in the fall or the limits in time of its passage through here 
on the return in spring. Great hordes pass during both seasons 
and varying numbers are present during the entire winter. All 
three forms intermingle here in winter, as, on at least one occa- 
sion, specimens of all three have been taken from the same 
flock. 
