THE VOYAGES OF THE LEMMING 
not usually, specimens at the Zoo. It is a curious fact 
thata peculiar long-tailed porcupine of the Old World 
has such a habit of ridding itself of that tail by mis- 
adventure, that the original specimen was ineptly called 
Trichys lipura. 
THE LEMMING 
There are several kinds of lemmings, at fewest two, 
which are circumpolar in range, and are found in the 
extreme of North America and Greenland, in Siberia and 
the north of Europe. They are little rodents, especially 
closely allied to the real water-rat, or vole, and belonging 
like that rodent, to a great family Muride, which em- 
braces anything and everything that can be really 
termed arat. The most familiar kind of lemming is the 
little animal which lives in the central highlands of 
Norway, and whose migrations are referred to in every 
book on popular zoology. It has been an inmate of the 
Zoo, though at the moment of writing there are no ex- 
amples of it. So associated is this little beast with its 
restless and persevering habits, that but a trifle is known 
about it when really at home in central Norway. The 
migrations seem to be associated with hunger ; unusual 
fertility produced lemmings in excess of available food. 
It is exactly the same thing that occasionally occurs with 
other rodents, more particularly with the field vole, of 
which there were phenomenal swarms in Scotland a few 
years back. When this event occurs, which is at quite 
irregular intervals, the lemmings put their best foot 
forward and set forth on their journey. So suddenly, and 
in such hordes, do they appear, that in old days they 
were held to be rained from the skies, as many persons 
believe with regard to frogs at the present day. They 
cross streams, descend and ascend cliffs, on their journey- 
ings, and in fact are impeded by no obstacle surmount- 
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