54 
Animals of the deer kind frequently take to the water, 
especially in the rutting season, when the stags are seen 
swimming for several leagues at a time, from island to 
island, in search of the does, especially in the Canadian 
lakes; and in some countries where there are islands near 
the sea-shore, they fearlessly enter the sea, and swim to 
them. In hunting excursions, in North America, the elk 
of that country is frequently pursued for great distances 
through the water. 
The large herbiverous animals, which are gregarious, can 
never remain long in a confined region, as they consume 
so much vegetable food. The immense herds of bisons 
which often, in the great valley of the Mississippi, blacken 
the surface near the banks of that river and its tributaries, 
are continually shifting their quarters, followed by wolves 
which prowl about in their rear. ‘It is no exaggera- 
tion,’’ says Mr. James, ‘‘ to assert, that in one place, on 
the banks of the Platte, at least ten thousand bisons burst 
on our sight in an instant. In the morning, we again 
sought the living picture, but upon all the plain, which last 
evening was so teeming with noble animals, not one re- 
mained.”” 
Besides the disposition common to the individuals of 
every species slowly to extend their range in search of 
food, in proportion as their numbers augment, a migratory 
instinct often developes itselfin an extraordinary manner, 
when, after an unusually prolific season, or upon a sudden 
scarcity of provisions, great multitudes are threatened by 
famine. We shall enumerate several illustrations of these 
migrations, because they may put us upon our guard 
against attributing a high antiquity to a particular species, 
merely because it is diffused over a great space; they 
show clearly how soon, in a state of nature, a newly-created 
species might spread itself, in every direction, from a sin- 
gle point. 
In very severe winters, great numbers of the black 
bears of America migrate from Canada into the United 
States; but in milder seasons, when they have been well 
fed, they remain and hybernate in the north. The rein- 
deer, which in Scandinavia can scarcely exist to the south 
of the sixty-fifth parallel, descends, in consequence of the 
greater coldness of the climate, to the fiftieth degree, in 
Chinese Tartary, and often roves into a country of more 
southern latitude than any part of England. 
In Lapland, and other high latitudes, the common 
squirrels, whenever they are compelled, by want of provi- 
sions, to quit their usual abodes, migrate in amazing num- 
bers, and travel directly forwards, allowing neither rocks, 
forests, nor the broadest waters, to turn them from their 
course. Great numbers are often drowned in attempting 
to pass friths and rivers. In like manner, the small Nor- 
THE CABINET OF NATURAL HISTORY, 
way rat sometimes pursues its migrations in a straight line 
across rivers and lakes; and Pennant informs us, that 
when, in Kamtschatka, the rats become'too numerous, they 
gather together in the spring, and proceed in great bodies 
westward, swimming over rivers, lakes, and arms of the 
sea. Many are drowned or destroyed by water-fowl or 
fish. As soon as they have crossed the river Penchim, at 
the head of the gulf of the same name, they turn south- 
ward, and reach the rivers Judoma and Ochot by the mid- 
dle of July, a district surprisingly distant from their point 
of departure. 
The lemings, also of Scandinavia, often pour down in 
myriads from the northern mountains, and devastate the 
country. They generally move in lines which are about 
three feet from each other, and exactly parallel, and they 
direct their march from the north-west to the south-east, 
going directly forward through rivers and lakes, and when 
they meet with stacks of hay or corn, gnawing their way 
through them instead of passing round. 
Vast troops of the wild ass, or onager of the ancients, 
which inhabit the mountainous deserts of Great Tartary, 
feed, during the summer, in the tracts east and north of 
Lake Aral. In the autumn they collect in herds of hun- 
dreds and even thousands, and direct their course towards 
the north of India, and often to Persia, to enjoy a warm re- 
treat during winter. Bands of two or three hundred quag- 
gas, a species of wild ass, are sometimes seen to migrate 
from the tropical plains of southern Africa to the vicinity 
of the Malaleveen river. During their migrations they 
are followed by lions, who slaughter them night. by 
night. 
The migratory swarms of the springbok, or Cape ante- 
lope, afford another illustration of the rapidity with which 
a species, under certain circumstances, may be diffused 
over acontinent. When the stagnant pools of the immense 
deserts south of the Orange river dry up, which often hap- 
pens after intervals of three or four years, myriads of 
these animals desert the parched soil, and pour down like 
a deluge on the cultivated regions nearer the Cape. The 
hayoe committed by them resembles that of the African 
locusts; and so crowded are the herds, that ‘‘the lion has 
been seen to walk in the midst of the compressed pha- 
lanx with only as much room between him and his victims 
as the fears of those immediately around could procure by 
pressing outwards.” 
Dr. Horsfield mentions a singular fact in regard to the 
geographical distribution of the Mydaus meliceps, a kind 
of polecatinhabiting Java. This animal is confined exclu- 
sively to those mountains which have an eleyation of more 
than seven thousand feet above the level of the ocean: 
on these it occurs with the same regularity as many 
