THE STOAT. 291 



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 acknowl- 

 edged to be true. Besides the various well-attested examples which are on record, I am 

 enabled to give my own personal testimony to the truth of this singular phenomenon, as I have 

 frequently seen a person whose hair was changed in a single night from dark to gray by sudden 

 grief and terror, and the whole system fatally deranged at the same time. 



Where the lowest temperature is considerably above that of the ordinary wintry degrees, 

 the Stoat is very uncertain in its change of fur, and seems to yield to or to resist the effects of 

 the cold weather according to the individuality of the particular animal. 



In the autumn, when the Stoat is beginning to assume its wintry dress, and in the spring, 

 when it is beginning to lose the snowy mantle of the wintry months, the fur is generally found 

 to be marked with irregular patches of dark and white spots, the sides of the face appearing 

 to be especially variable in this respect. Sometimes the animal resists the coldest winters, 

 and retains its dark fur throughout the severest weather, and it sometimes happens that a 

 Stoat will change its fur even though the winter should be particularly mild. Mr. Thompson 

 records, in Ms work on the Natural History of Ireland, that he saw a Stoat which was cap- 

 tured on the 27th of January, 1846, which was wholly white, with the exception of a brown 

 patch on each side of its face. Yet the winter had been remarkably mild, without any frost 

 or snow, although there had been abundance of rain and storms. Two white Stoats were 

 killed in Ayrshire, in 1839, which were almost entirely white, though the frosts had been 

 extremely mild, and the snow had altogether been absent. 



As, in the former of these examples, the weather is said to have been extremely wet, it 

 may be presumed that the moisture of the atmosphere and ground may have some connection 

 with the whitening of the hair. On account of the better radiating powers of dark substances, 

 the dew or general moisture is always found to be deposited in greater quantity on dark or 

 dull, than on white or polished substances. Any one may easily prove this fact, by watching 

 the effects of the dew on a white and a red rose growing in close proximity to each other. 



The Stoat is considerably larger than the weasel, measuring rather more than fourteen 

 inches in total length, of which the tail occupies rather more than four inches. There is, how- 

 ever, considerable difference in the size of various individuals. 



It is a most determined hunter, pursuing its game with such pertinacious skill that it very 

 seldom permits its intended prey to escape. 



