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winter in Wyoming, near the hot springs, whose warmth keeps the neigh- 
boring waters and ground from freezing. Nevertheless, it is as yet un- 
explained why some birds, notably many of the warblers, retire in winter 
to such a great distance south, some even crossing the equator and pass- 
ing several hundred miles beyond. Certainly neither cold nor hunger 
can be the cause of such wanderings. 
It has been often noticed that during the fall migration many birds 
seem to be able to foretell the approach of storms from the north, and 
hurriedly depart southward, before human eyes can detect any signs of 
the coming change. There is a large accumulation of evidence on this 
point, all seemingly in support of the proposition which has been for- 
mulated by one of our leading ornithologists in the following words: 
“Birds discern approaching meteorological changes.”* Some ornithol- 
ogists deny this, saying that in such cases the birds have out-traveled 
the storm, in which they were at first caught, their superior powers of 
flight enabling them to pass ahead of it; or that they have been warned 
by the hasty approach of more northern birds coming from the area 
over which the storm was moving. , 
If we study fall migration merely, there seems to be no doubt of the 
trath of this statement, but if we include spring migration the question 
becomes much more involved. If birds discern approaching meteor- 
ological changes, why is it that so many thousands perish each year 
by being caught in storms and frozen to death? Certainly an approach- 
ing storm in spring must give just as plain and early a warning as one 
in the fall, yet the same birds which are said to foresee it at the latter 
time and escape, rush blindly forward a few months later and are over- 
taken, their death paying the penalty of their rashness. The hardy 
waterfowl (Ducks and Geese) push northward in the spring, encounter 
storms, and are turned back, only to repeat the same thing a dozen 
times before they reach their summer quarters, but each time, instead 
of avoiding the approaching storm, they do not retreat until its actual 
presence drives them back. If they can foresee these changes, then 
their love of home and their desire to return to it must be wonderfully 
strong. . 
SPEED AT WHICH BIRDS MIGRATE. 
In studying the speed at which birds proceed northward in their mi- 
grations one.is beset by many difficulties. To determine the compara- 
tive speed of the several species is easy enough, but to determine the 
absolute rate—the exact number of miles which a particular bird makes 
during one day’s journey—is beyond our power. If migration were a 
steady movement northward, with the same individuals always in the 
van, numerous careful observations might make it possible to arrive at 
an approximation to the truth; but instead of this, migration is per- 
formed something after the manner of a game of leap-frog.. While in 
*J. A. Allen, in Scribner’s Monthly Magazine for October, 1881, p. 938, 
