MAMMALS OF MINNESOTA. 115 
‘houses of the fur traders, where it may be heard the live-long 
night pursuing the white-footed mouse. Up toacertain limit of 
latitude it would appear to increase in numbers to the north- 
ward. The abundance of an Ermine, either the present or suc- 
ceeding species, on the Missouri is attested by the regalia of 
ceremony of some of the Indian tribes—picturesque constumes 
decorated with the tails, in rude imitation of royal fashion. 
Like a majority of thoroughly predacious animals, the Ermine 
is somewhat nocturnal; that is to say, it is active and success- 
fulinthe dark. Nevertheless, it is too often abroad in the day- 
time, either in sport or on the chase, to warrant our reckoning 
it among the truly nocturnal Carnivores. In the choice and 
construction of its retreats we see little evidence of burrowing 
instincts, or, indeed, of any considerable fossorial capacity. It 
retreats beneath stone heaps, under logs and stumps, in hol- 
lows of trees, and also in true underground burrows, though 
these. it should be observed, are usually those made by Rodents 
or other burrowers whom it has driven off or destroyed. Nev- 
ertheless, there is evidence that the animal sometimes digs. 
Thus Captain Lyon, as rendered by Richardson, states, that he 
observed a curious kind of burrow made by Ermines in the snow, 
‘which was pushed up in the same manner as the tracks of 
moles through the earth in England. These passages run in a 
serpentine direction, and near the hole or dweling place the 
circles are multiplied, as if to render the approach more intri- 
cate.” Audubon has a passage of similar effect:—‘‘We have 
frequently observed where it had made long gallleries in the 
deep snow for twenty or thirty yards, and thus in going from 
one burrow to another, instead of travelling over the surface, it 
had constructed for itself a kind of tunnel beneath.” 
Accounts of different writers indicate a great variation in the 
number of young produced at a birth—from two totwelve. We 
may safely assume that these unusual extremes, the aver- 
age litter being five or six. As in caseof the Mink, the rutting 
season is early; in the United States, during a part of Febru- 
ary and March. Young have been noted, toward the southern 
extreme of the range of the species, before the end of March; 
but most are produced in May or late in April. Without defi- 
nite information respecting the period of gestation, we may sur- 
mise this to be about six or seven weeks. Information is also 
wanting of the length of time that the young nurse or require 
to have food brought them by the parents. 
