CLASS I. MAMMALIA: ORDEE Y. RODENTIA. 
429 
about seven inches long, with a tail half an inch. It burrows in the earth, making its nest of 
moss ; from four to eight young arc produced twice a year ; its color is yellow, variegated with 
black. It is sometimes called the Norwa^j Rabbit. It is celebrated for its occasional migrations 
— that is, once in four to ten years — ^in immense numbers. They proceed in a straight line, a few 
yards apart, each one usually tracing a shallow furrow in the soil as he goes. They devour all the 
herbs and roots in their passage. If they come across a man they glide between his legs ; if they 
meet with a hay-stack they gnaw through it ; if they come to a rock they go round it in a semi- 
circle, and then resume the straight line of their march. On coming to a lake or river, or an arm 
of the sea, they swim directly across ; if they encounter a boat they climb over it, so as not to be 
diverted from their advance in a direct line. It is curious that they avoid the habitations 
of men. They proceed by night and halt by day. Woe to the place where they stop, for in 
a few hours meadows, gardens, and corn-fields are dry and barren as if scorched by fire. As 
they take the inhabitants by surprise, no effectual defense can be offered. They resist fiercely, 
and will bite the stick or hand that removes them, crying and barking like little dogs, when 
defending themselves. Multitudes of them are, hoAvever, destroyed in their progress by man. 
It is asserted that among them a female may be often seen with one young one in her mouth 
and another on her back. The number that proceed in this manner is beyond computation. 
They descend in tAvo directions from the Scandinavian Alps, which are their native home, one 
stream directing its march from east to west toward the North Sea; the other from west to east 
toward the Gulf of Bothnia. After a time they set out to return, but their numbers are so re- 
duced that they are scarcely observed. Very few survive to reach the mountain homes from 
which they departed. The cause of these migrations is utterly inscrutable. They seem to pro- 
ceed from some instinct that acts like an uncontrollable destiny, urging them on through difficulty, 
danger and suffering to an inevitable doom. In general, the instincts of animals are seen to 
be founded in truth and reason, and to conduce to the advantage of the creatures on whom they 
act; but in this case it seems like an hallucination, and ends in destruction. The migrations of 
the gray squirrels of the United States have some analogy to these we are describing, but they 
THE LAPLAND LEMMING. 
may reasonably be supposed to be the result of a general necessity in respect to food; but no 
such explanation is possible in respect to the Lapland Lemmings. It has been suggested that 
by a mysterious but still prophetic instinct, they are advised of the approach of a winter of 
unusual severity, and that they migrate to avoid it. Thus it is stated, that in 1742 avast migra- 
