402 MICHIGAN BIRD LIFE. 
infrequently hovers before a twig or leaf and snaps up small insects which 
appear to be stationary, sometimes descending to the grass for this purpose. 
Its food habits on the whole may be considered beneficial, though not 
markedly so. Three specimens, taken in an orchard in Illinois which was 
being destroyed by canker worms, were examined by Professor 8. A. 
Forbes and found not to have eaten any of the caterpillars, the stomachs 
containing more than 50 per cent of flies and gnats, with various harmless 
beetles and a few ants with other hymenoptera. In Nebraska Professor 
Aughey found seven grasshoppers and many other insects in the single 
specimen which he examined. 
TECHNICAL DESCRIPTION. 
Adult: Dark olive above, darkest on top of head; under parts whitish, washed on sides 
and across breast with the color of the back, and sometimes tinged with yellow on the 
belly; wings brownish-black with two more or less distinct bars formed by the whitish tips 
of the greater and median coverts; tail plain brownish black; upper mandible dark brown, 
lower yellowish; feet black; iris brown. In general appearance much like the Olive-sided 
Flycatcher, but decidedly smaller, lacks the cottony flank tufts, and does not show the 
mottling due to dark-centered feathers. 
Length 5.90 to 6.50 inches; wing 3 to 3.45; tail 2.50 to 2.90; culmen .43 to .52. 
183. Yellow-bellied Flycatcher. Empidonax flaviventris (Baird). (463) 
Synonyms: Tyrannula flaviventris, M. W. & 8. F. Baird, 1843.—Muscicapa flaviventris, 
Aud., 1844.—Empidonax flaviventris, Baird, 1858, and most authors. 
The only one of the small flycatchers which is distinctly yellow below 
in the spring; in the autumn it is not readily separated by this mark from 
several other species. 
Distribution.—Eastern North America, west to the Plains, and from 
southern Labrador south through eastern Mexico to Panama, breeding 
from the northern states northward. 
In Michigan this bird occurs sparingly during the migrations, passing 
northward during May, and southward during August and September. 
It is so seldom noticed that average dates of occurrence cannot be given. 
Swales calls it a common migrant at Detroit, giving May 7, June 9, August 
12, and September 27 as extreme dates. While with us there seems to be 
nothing in its habits which serves to distinguish it particularly from the 
other species which it so much resembles. It is likely to be found in low 
growths and in moist woodlands, and feeds principally on insects caught 
on the wing. 
Its nesting habits are peculiar, since, unlike any other native flycatcher, 
the nest is always placed on the ground. Usually a mossy knoll or fern- 
covered bank is selected and the nest is sunken to its edge and not in- 
frequently roofed over and reached by a short passage from the outside. 
The nest consists largely of mosses, fern stems and slender roots, and the 
eggs, usually four, are white, finely marked with dots of brown, mainly 
about the larger end. They average .73 by .51 inches. 
We have no record of a Michigan nest of this species, yet it is extremely 
probable that the bird breeds occasionally in the higher parts of the Lower 
Peninsula and throughout a considerable extent of the Upper Peninsula. 
It seems to be nowhere an abundant species and the scattered individuals 
seen in midsummer in these localities might easily breed without the nest 
being discovered. Mr. T. B. Wyman writes that it is a frequent summer 
