40 BIRDS OF LA PLATA 
reconciled to the Owls, but perpetually flutter about 
them, protesting against their presence with long 
complaining notes. 
The nest, made of dry grass lined with feathers, 
is placed at the extremity of the long, straight, 
cylindrical burrow, and contains five or six white 
pointed eggs. I have never seen these Martins 
fighting with the Minera to obtain possession of the 
burrows, for this industrious little bird makes itself 
a fresh one every spring, so that there are always 
houses enough for the Martins. After the young 
have flown, they sit huddled together on a weed or 
thistle-top, and the parents continue to feed them 
for many days. 
As in size and brightness of plumage, so in language 
is the Bank-Martin inferior to other species, its only 
song being a single weak trilling note, much pro- 
longed, which the bird repeats with great frequency 
when on the wing. Its voice has ever a mournful, 
monotonous sound, and even when it is greatly 
excited and alarmed, as at the approach of a fox or 
hawk, its notes are neither loud nor shrill. When 
flying they glide along close to the earth, and fre- 
quently alight on the ground to rest, which is 
contrary to the custom of other Swallows. Like 
other species of this family, they possess the habit 
of gliding to and fro before a traveller’s horse, to 
catch the small twilight-moths driven up from the 
grass. A person riding on the pampas usually has a 
number of Swallows flying round him, and I have 
often thought that more than a hundred were before 
