290 CLASS MAMMALIA. 



when the fur is greatly esteemed and in much request, parti- 

 cularly for ornamenting habiliments of office and dignity. 



This extraordinary mutation of colour, however, is nearly 

 confined to those individuals that are met with in high la- 

 titudes, as in Norway and Siberia : but the Stoat, which 

 is very common in England, is seldom found white in this 

 country, though in the winter it is occasionally seen here, 

 and more frequently in Scotland, in a sort of intermediate 

 condition, appearing to be assuming the pure white dress, 

 yet as if the force of the cause, whatever it is, were insuf- 

 ficient to do its office completely. BufFon had one of these 

 animals brought to him in its white dress. He kept it con- 

 fined, and observed the change of colour, which commenced 

 early in March, and was completed by the 17th of that 

 month. The animal died afterwards, in consequence, as is 

 stated, of substituting milk for its diet instead of flesh. 



It is surely a task well worthy the attention of the phy- 

 siologist, to ascertain the exciting cause, as well as the 

 mode, by which this strange operation of nature on an 

 animal body is produced, We have data enough to con- 

 clude, perhaps, that it is the result of climate, since it is 

 observed in those animals chiefly, if not wholly, which are 

 found in the Polar regions ; we know also that the new 

 colour is produced together with a new coat or fur, but 

 why the new fur should reflect rays differing from the old 

 is not explained ; in short, we seem as yet to be quite in 

 the dark as to the excitement, the mode of operation, and 

 the object intended. 



The habits of the Stoat correspond in general with those 

 of the Polecat, though, being smaller, it is less capable of 

 mischief. It will eagerly attack a rat, and soon overcomes 

 and kills it by an almost imperceptible wound in the head 

 or throat. 



Captain Ross, in his voyage of discovery, found an Er- 

 mine in lat. 73° 37', where it must necessarily have been 

 exposed to an intense degree of cold. 



