BELL’S VIREO STUDIES 
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lowed to hang down. Then coarser materials, such as grasses, 
were laid across the crotch about 2% inches from the angle 
This was to form the unsupported edge of the nest which was 
built up relatively strong. At this stage most of the material 
was at this unsupported edge. 
The art of nestbuilding from this point has not been worked 
out by the writer any more than for him to realize that there 
is much of vital interest to be learned from a further study of 
it as practised by the Bell’s Vireo. How the bird weaves the 
nest material in and out, how the grasses are made to cling to 
Fig. 43. — The typical Bell's Vireo’ s nest is always hung from a low 
horizontal crotch. It is made of leaves, grasses and plant fibers very com- 
pactly woven together. The eggs are pure w'hite with a few small brown 
spots mostly at the larger end. 
the branches, and how a definite shape is given to the mass 
under such trying circumstances are all questions yet to be 
worked out. 
The completed nest -of the Bell’s Vireo is somewhat different in 
shape from that of some of the other vireos. Whereas the War- 
bling and Yellow-throated build rather shallow hanging struc- 
tures, those of the Red-eyed and Bell’s are deeper and more 
bulky. Such a structure, as illustrated by nest number two 
