366 THE STOAT. 



The change of color which takes place during the colder months of the year is now 

 ascertained, with tolerable accuracy, to be caused by an actual whitening of the fur, 

 and not by the gradual substitution of white for dark hairs, as was for some time 

 supposed to be the case. 



The hairs are not entirely white, even in their most completely blanched state, but 

 partake of a very delicate cream-yellow, especially upon the under portions, while the 

 slightly bushy tip of the tail remains in its original black tinting, and presents a singular 

 contrast to the remainder of the fur. In these comparatively temperate latitudes, the 

 Stoat is never sufficiently blanched to render its fur of any commercial value, and the 

 hair appears to be longer, thicker, and whiter in proportion to the degree of latitude 

 in which the animal has been taken. As may be supposed, from the extreme delicacy 

 of the skin in its wintry whiteness, the capture of the Stoat for the purpose of obtaining 

 its fur is a matter of no small difficulty. The traps which are used for the purpose 

 of destroying the Stoat are formed so as to kill the animal by a sudden blow, without 

 wounding the skin ; and many of the beautiful little creatures are taken in ordinary 

 snares. 



The object of the whitened fur of the Stoat is popularly supposed to be for the 

 purpose of enabling the animal to elude its enemies by its similarity to the snow- 

 covered ground on which it walks, or to permit it to creep unseen upon its prey. It 

 seems, however, that many animals partake of the same tinting, some of which, such 

 as the polar bear, are so powerful, that they need no such defence against enemies, 

 and so active in the pursuit of the animals on which they feed, that their success in 

 obtaining food seems to depend but little upon color. The arctic fox, which has 

 already been mentioned on page 336, and the lemming, which will be recorded in a 

 future page, are examples of this curious mutation of color. 



Putting aside for the present the mode in which the fur changes its color, the real 

 object of the change appears to be for the purpose of defending the wearer against 

 the intense colds which reign in those northern regions, and which, by a beautiful 

 provision, are obliged to work the very change of color which is the best defence 

 against their powers. It is well known that black substances radiate heat more 

 effectually than objects which are bright and polished. This fact is popularly shown 

 in the bright teapots with which we are so familiar, and which are known, by practical 

 experience, to retain the heat for a much longer period than if their surface had been 

 roughened or blackened. 



The reader will not fail to remark a certain coincidence between the snowy hairs 

 that deck the frosty brows of old age with a reverend crown and the white fur that 

 adds such beauty to the frost-beset Stoat. It may be that the energies of the animal 

 are forced, by the necessity which exists for resisting the extremely low temperature of 

 those icy regions, to concentrate themselves upon the vital organs, and are unable to 

 spare a sufficiency of blood to form the coloring matter that tinges the hair. There is 

 evidently an analogy between the chilly feeling that always accompanies old age and 

 the frosty climate that causes the Stoat's fur to whiten. 



It is well known that examples of albinos occur in almost every kind of quadruped 

 and bird, and it seems probable that the deprivation of color is in very many cases 

 owing to the weak constitution of the individual. One of these albinos was a bird, 

 which was caught and tamed, and although it was of a cream color when it was 

 captured, yet assumed the usual dark plumage of the species at the first moulting 

 season that occurred after its capture. As the bird also appeared to be much more 

 healthy and lively than when it was clad in white feathers, it seems likely that the 

 albino state may have been caused by weakness of constitution. 



It is clear that, whatever may be the immediate cause of the whitening of the hair, 

 the change of tint is caused by the loss of the coloring matter which tinges the hair, 

 and that there must be some connection between the frost-whitened Stoat, the age- 

 whitened human hair, and the abnormal whiteness of various albinos. I would also 

 mention, in connection with this subject, the curious instances where the hair of human 

 beings has been suddenly blanched by powerful emotion. This fact has been disputed 

 by several physiologists, but is now acknowledged to be true. Besides the various 



