49 R. COLLETT. 


13. Nature and Habits during Migration. — 
In ordinary years the lemmings live quietly and obscurely 
on the mountain plateaux, and one may wander over long 
stretches, in which they really occur by no means sparsely, 
without coming across a single individual. 
But during prolific years their behaviour alters. They are 
busy also in the daytime, and incessantly attract attention by 
their unceasing rambles amongst the tussocks and serub. 
When once they have arrived down in the lowlands it is 
impossible for one to avoid meeting them at every turn. They 
do not endeavour to conceal themselves; they appear in the most - 
unaccouptable places; enter, without any apparent shyness, the 
streets of towns, and even the houses, until they fall åa prey to 
the dogs, cats, and human beings. During the migration of 
1862, I saw individuals running up the high granite stairs in 
the vestibule of the university at Christiania, as if it were their 
intention to exhibit themselves in the museum. In 1876, they 
were so numerous in all the coast towns between the Christiania 
Fjord and Christiansand, that, fin the town of Arendal, the first 
thing to be done every morning was to collect the bodies of 
lemmings in the streets and in the court-yards of the houses, 
that had been killed by cats during the night.” 1 
During these migrations they appear to forget every sense 
of danger. They wander irresistibly on, often falling headlong 
down slopes or holes from which they cannot ascend and 
where, occasionally, their bodies may be found in heaps*. 
During winter they burrow long tunnels under the snow, 
and may often be seen running for short distances on its sur- 
1 Somerville, Proc. Zool. Soc. Lond. 1891, p. 656. 
Å similar feature has been observed in M. schisticolor. During mi- 
gratory years very many of this latter species may be found dead, 
when their path has led across å cleft in the rocks (for instance the 
cutting of a road or railway), during which they have, as it were, 
marched out into space and been precipitated to the ground beneath. 
ro 
