50 TRICHOLOGIA MAMMALIUM ; 
slightest touch of the hair is often sufficient to cause violent pain, which seems to be in the 
hair itself, but the sufferer, (who is very intelligent,) has no doubt of its being confined to 
the scalp. 
Or VesseLs.—In the course of our pile manipulations we have often encountered small 
threads, which may be vessels or nerves, but which are too small to be identified under the 
microscope ; some of these are attached to the posterior portion of the button, when drawn 
out, and others upon the same part of the follicles, obtained by dissection or maceration. 
Figure 56 represents a hair of the oval-haired species, with a button somewhat deviating 
from the normal shape, but with small portions of four threads disrupted in the drawing. 
Figure 24, which represents a hair of the pavilion of the external ear, shows threads. 
So does figure 29, which represents a hair of the axille. Figure 31, which represents the 
hair of the forearm, exhibits a thread, (see ‘“‘a.”) The same may be said of figure 55, ‘“e.” 
Note.—In the drawings of hairs, in Wilson’s Human Physiology, it is represented that 
each filament has two sebaceous glands opening by short ducts, one on each side thereof ; 
but we have not found them in place. 
From all which, we agree with Henle that common hairs, (by which term he excludes 
the whiskers of the lower animals,) although ansensible themselves, because they are desti- 
tute of nerves, are in connection, through their roots, with a tissue rich in nerves and 
sanguiferous vessels. (See Gen. Anat., v. 1., ch. iv., p. 300.*) 
As the hair subsists from vessels, so ¢hey are influenced by the vital force and health of 
the individual ; so that when we see a head thickly covered with strong, richly colored, 
lustrous hair, we may predict, that the person is in good health; but when the hair is 
weak, sparse, dull shades of color and devoid of lustre, we may as surely pronounce, that 
there exists some bodily infirmity, or that there is a diseased state of the system. 
Or THe SEecreETION oF Pite.—Admitting that there is no vitality in the shaft of a 
common hair, still it may be an organ of secretéon. The pile of a healthy person is almost 
always annointed, as it were, with an oleagenous substance; which is believed to be of 
that character. In that dreadful disease, mzlk sickness, the hair sometimes drops out, and 
in proof that the virus enters into the body of the filament, Bowyer assures us that it has 
been detected in hair and wool, after they have been cleansed, in the usual manner, and 
have been woven into cloth. Prof. John K. Mitchell, M. D., is of opinion that this class of 
diseases is caused by poisonous fungi, one variety of which resides dnsde of the follicle, 
between its walls and the button, and that it ascends to the epidermis. (See Mitchell on 
Fevers, p. 65 to 67.) And Mr. Youatt says that what is termed the yolk of sheep’s wool, 
is a secretion. 
* See Youatt in Essay on Sheep, Lib. of Usf. Know. 
