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IOWA ACADEMY OF SCIENCE Voi.. XXVIII, 1921 
Cowbird. Molothrus a. ater (Bodd.). Still another item of 
ornithological interest that is likely to thrust itself upon the ob- 
server’s attention in such a region as the one here discussed is the 
prevalence of the parasitic habit on the part of the cowbird and 
the general infliction of its presence, eggs and young upon num- 
erous species of birds. Either the eggs or young of this polyga- 
mous and polyandrous outcast of the Icteridae were found in 
nests of Vireosylva olivacea on two occasions, Hylocichla guttata 
pallasi on two occasions and Junco h. hyemalis on one occasion. 
In this latter nest two cowbirds and one junco were waging the 
struggle for existence with the odds in favor of the former, which 
were larger, stronger and much more active than was the rightful 
occupant of the nest. 
Cliff Swallow. Petrochelidon 1. lunifrons (Say). Cliff swal- 
lows, along with barn swallows, commonly nest under the eaves 
of some of the buildings at Ingleside, a small resort on the north 
shore of the lake. In all, fourteen young of the former species, 
which occupied six nests, were banded between July 15 and 
August 6. These birds were in various stages of development at 
the time of banding. In one group of three nestlings banded on 
July 24, two bore dipterous larvae of some kind upon the soles 
of their feet; one of these birds carried two of the larvae which 
were about 8 mm. in length and fully gorged with blood. In no 
other birds examined during the summer was a similar condition 
observed. 
Hermit Thrush. Hylocichla guttata pallasi (Cab.). On July 
Fig. 29. Two nests of Hermit Thrush less than a foot apart; the occupied one 
contains three eggs of this species and one cowbird’s egg. 
