s tail; and that, for about an inch or so at the tip, was covered with
black silky hair. On some parts of the body, too, the white was tinged
with a primrose yellow; but this tinge is not found in all animals of
this species, as some individuals are pure white. Of course it was now
in its winter "robes;" but in the summer it changes to a colour that
does not differ much from that of the common weasel.

When Lucien first saw it, it was running along the top of the wreath,
and coming from the same direction from which the mouse had come. Now
and then it paused awhile, and then ran on again. Lucien observed that
it kept its nose to the ground, and as it drew nearer he saw that it was
following on the same path which the other had taken. To his
astonishment he perceived that it was _trailing the mouse_! Wherever
the latter had doubled or made a _detour_, the ermine followed the
track; and where the mouse had given one of its long leaps, there the
ermine would stop, and, after beating about until it struck the trail
again, would resume its onward course at a gallop. Its manoeuvres were
exactly like those of a hound upon the fresh trail of a fox!

Lucien now looked abroad to discover the mouse. It was still in sight
far off upon the snow, and, as Lucien could see, busily gnawing at the
arbutus, quite unconscious that its _greatest_ enemy was so near. I say
greatest enemy, for the _Mus leucopus_ is the _natural_ prey of the
_Mustela erminea_.

The mouse was soon made aware of the dangerous proximity, but not until
the ermine had got within a few feet of it. When it perceived the
latter it shrunk, at first, among the leaves of the arbutus; but seeing
there would be no protection there--as the other was still springing
forward to seize it--it leaped up, and endeavoured to escape by flight.
Its flight appeared to be in alternate jumps and runs, but the chase was
not a long one. The ermine was as active as a cat, and, after a few
skips, its claws were struck into the mouse. There was a short, slender
squeak, and then a "crunch," like the cracking of a hazel-nut. This
last sound was produced by the teeth of the ermine breaking through the
skull of its victim.

CHAPTER THIRTY FOUR.

THE ARCTIC FOX AND WHITE WOLF.

Lucien turned round to get hold of his rifle, intending to punish the
ermine, although the little creature, in doing what it did, had only
obeyed a law of nature. But the boy had also another design