The pale hairs had more air-spaces than the darker ones.

There was much structural change in the brain and spinal cord.
Smyly of Dublin reported a case of suppurative disease of the temporal bone, in which the hair changed from a mouse-color to a reddish-brown; and Squire records a congenital case in a deaf mute, in whom the hair on the left side was in light patches of true auburn and dark patches of dark brown like a tortoise-shell cap; on the other side the hair was a dark brown.

Crocker mentions the changes which have occurred in rare instances after death from dark brown to red.
Chemic colorations of various tints occur.

Blue hair is seen in workers in cobalt mines and indigo works; green hair in copper smelters; deep red-brown hair in handlers of crude anilin; and the hair is dyed a purplish-brown whenever chrysarobin applications used on a scalp come in contact with an alkali, as when washed with soap.

Among such cases in older literature Blanchard and Marcellus Donatus speak of green hair; Rosse saw two instances of the same, for one of which he could find no cause; the other patient worked in a brass foundry.
Many curious causes are given for alopecia.