194 ‘THE ZOOLOGIST. 
heard of a great many. Few reach the birdstuffers until after the 
severe weather, for Ermine Stoats escape notice until after the 
snow is gone, when they become very conspicuous. 
An interesting question is-—-Would a Stoat turn white in a 
winter in which absolutely no cold weather (say, nothing below 
30°) occurred? It is worth remembering that during this mild 
season of 1897-8 we had a few days of sharp frost in the latter 
end of December, with a good deal of white rimy frost. On two 
nights I registered 22° at four feet from the ground on a north 
wall, and on four days it froze all day on the ground in the shade. 
The change to ermine dress is produced by the white of the 
belly extending up the sides of the body and over the limbs, until 
only the top of the head and a band down the middle of the back 
remain brown. The white then spreads across the lower part of 
the back (leaving for a time, in some cases, a detached portion of 
brown near the root of the tail); the spinal line becomes gradually 
shorter and narrower, and at last disappears. Meanwhile the 
white on the head has increased, the ears and the region about 
them have become white, and a space round the eyes and a patch 
on the top of the head alone remain brown. The latter dis- | 
appears, and the patches about the eyes decrease, until only a | 
narrow ring of brown round each eye is left. This is actually 
the last part to turn white. Stoats in this condition have a 
*“‘spectacled” appearance; I have handled several. One was 
caught at the end of February or beginning of March, 1891, and 
another on March 5th, 1894. | 
In ‘The Zoologist’ for 1888, p. 140, I published some 
observations which pointed to the fact that the change from 
white to brown was effected by a change of colour in the fur, 
and not by a change or moult of the hairs; and that the change | 
began at the tip and not at the base of the hairs. I believe that | 
the change from brown to white is also effected by a change in | 
colour of the hairs, and not by a change in the coat. A change | 
of coat in severe weather would be inconvenient for the animal. 
