BIRDS OF MINNESOTA. 355 
nesting habits of this beautiful swallow which has been noticed 
so much of late years, I believe to have been associated with 
its entire history, and is abundantly verified here. 
SPECIFIC CHARACTERS. 
Glossy metallic green above; entirely white beneath; nos- 
trils basal, small, oblong, and covered by a membrane; tail 
emarginate; tarsus naked and shorter than the middle toe, and 
scutellate. 
Length, 6.25; wing, 5; tail, 2.65. 
Habitat, North America at large. 
CLIVICOLA RIPARIA (L.). (616.) 
BANK SWALLOW. 
This smallest of the swallows, which avoids all intercourse 
with man, seeking its breeding places in the neighborhood of 
streams and lakes, often quite inaccessible, would be a hard 
Species to watch as to the times of their arrival and departure 
but for the circumstance of their spending their nights in their 
holes in the banks where they breed. When new holes have to 
be excavated, it is done very rapidly, so as to provide a place 
for the first night’s lodging. An early visit to the vicinity of 
the banks will determine their arrival. A single locality may 
be occupied by only a few birds, but many places within a short 
distance of each other are occupied by hundreds, if not thou- 
sands. The supply of food must in some measure determine 
that, although the possibilities of their wings may meet most 
emergencies of that kind. 
They reach the greater part of the State by the 5th of May as 
a general thing, and at once enter upon their nidification. The 
nest is usually at the end of a hole about half a yard in length, 
and consists of a cavity of sufficient dimensions to receive an 
ample quantity of dried grasses, hay, feathers and down of 
different kinds. Sometimes the nest is much further in the 
bank. 
They deposit four or five pure white eggs, and bring out two 
broods in due. time for the last to be ready for the southern 
migration by the 25th of August. 
Its nidification habits doubtless restrict its numbers in certain 
districts, but it is an abundant species. I have not failed to 
find it in every important section seen or heard from. 
SPECIFIC CHARACTERS. 
Smallest American swallow. Tail slightly emarginate, outer 
web of first primary soft, without hooks; lower part of tarsus 
