346 THE MIGRATION OF BIRDS. 
flying close to the ground to escape the fury of the blast, pas 
by so continuously that it was often impossible to tell where 
ended and the next began. For four or five hours the im 
hosts kept sweeping by; the air at times seemed filled with them 
and I was vividly reminded of Audubon’s account of the ‘wild — 
pigeons in Kentucky. The storm expended its fury within a few 
hours after the last blackbird had passed; but although the next — 
few days were clear and warm, not a bird reappeared for nearly & 
week. A similar migration of white-bellied swallows took place 
near Newark, New Jersey, some six or seven years since, in ; 
latter part of October, just before a long, northeast rainstorm, 
followed by sharp frosts. Although their numbers were not 
to those of the blackbirds, the sky at times, seemed fairly covere 
with their hosts, tens of thousands being in sight at any moment 
for nearly an hour. Their course was to the southwest; and as 
if aware of the impending storm, their flight was hurried an 
direct, far different from their usual circling, easy motion. = 
But the most remarkable instance of the kind that ever came 
across my observation occurred in southern Iowa, in the fall of 
1871. The weather, at the time, was the perfection of Indian, 
summer,—clear, bright and warm. About the tenth of November, 
vast numbers of cranes began to fly south. Always @ cor 
bird in spring and fall, they appeared in such multitudes, 
settlers, who had been in the country for twenty years Eid 
declared they had never seen anything to equal it. thou 
upon thousands covered the sky at all hours of the day, Hoat 
in slow easy circles, far up in the air all moving steadily § 
ward. Most of them were of the sandhill species; but here 
there, sweeping in wider circles far above their brown bret 
if conscious of their superior beauty, a flock of white ones 
peared,—a beautiful sight, their snowy plumage and black 
sharply outlined against the blue sky ; sometimes so high up 
they looked like mere white specks, and their loud rattling 
sounded like faint echoes of the whoops of those far beneath 
For three days the remarkable procession lasted; then p 
next two days, although the weather continued as warm p 
as it had previously been, not a crane was to be seen; 
that, without the slightest warning, a succession of o 
hail and rainstorms set in, followed by intense cold. On 
of November the mercury sunk to 5° F., and by the 4°" 
