258 LAND BIRDS 
The young or Cliff Swallows are fed by regurgitation 
of small insects. These are caught, scoop-net fashion, 
by the adults in flying through swarms of the gnats and 
other small winged insects that hover in the air morning 
and evening, or that dance in the sunshine of mid-day. 
Once every ten or fifteen minutes is the usual time for 
a meal, but the intervals are shorter early in the morning 
after the night’s fast, and late in the afternoon. 
617. ROUGH-WINGED SWALLOW. — Stelgidopteryx 
serripennis. 
Famity: The Swallows. 
' 
Length: 5.00-5.75. 
Adults: Upper parts dull grayish brown, darker on wings and tail ; ter- 
tials usually margined with grayish ; under parts plain brownish 
gray ; belly and under tail-coverts white. 
Young: Similar to adults, but plumage more or less tinged with brown ; 
wings with broad cinnamon tips and margins. 
Geographical Distribution: United States, from Atlantic to Pacific, and 
adjoining British Provinces ; migrates to Guatemala. 
California Breeding Range: Below Transition zone, east and south of 
humid coast belt. 
Breeding Season : May and June. 
Nest: In crevices of stone walls and bridges, and in holes in banks ; 
made of grasses and straws ; lined with a few feathers. 
Eggs: 3to06; white. Size 0.75 x 0.58. 
ALTHOUGH sometimes confounded with the bank 
swallow, the Rough-winged is slightly larger, lacks the 
sooty chest-band and clear white under parts, and has 
in addition the distinguishing serrated outer web of the 
outer primary. Both this variety and the bank swallow 
differ from the other members of their family in their 
