There has been much discussion as to whether this winter whitening is due to a change in the colour of the individual hairs or to a change of coat.
It has, however, been demonstrated that the senile whitening of human hair is due to the presence of phagocytes, which devour the pigment-bodies; and from microscopic observations recently made by the French naturalist Dr E.
The winter whitening of mammals is, therefore, precisely similar to the senile bleaching of human hair, no shift of the coat taking place.
By the end of October they had perished utterly at the hands of the Seljuks; a heap of whitening bones also remained to testify to the later crusaders, when they passed in the spring of 1097, of the fate of the people's Crusade.
Sticks (two or three yearling osiers) are also grown for whitening and buffing: the less ligneous varieties of S.