894 DR, E. KLEIN. 
After a great many negative results I have succeeded, in 
a few instances, in the human scalp as well as in that of the 
dog, to inject the ultimate lymphatics of the hair-follicles. 
Both in the asphalt-benzole injections, but especially in 
those with Berlin blue, I have ascertained that the lym- 
phatic vessels and interfascicular lymph-spaces of the 
connective tissue surrounding the hair-follicle bear an 
intimate and, I need hardly add, important relation to the 
latter. 
The fibrous coat of the hair-follicle, that is, the hair-sac 
proper, contains, both in the human hair as well as in that 
of the dog, more or less continuous lymph-channels, which 
are in communication with the plexus of the lymphatic 
vessels of the corium, and with the interfascicular lymph- 
spaces around. In a longitudinal section these lymph- 
channels are well seen in close neighbourhood to the outer 
root-sheath of the hair. In transverse sections it is ascer- 
tained that the lymphatics of the hair-sac surround lke a 
sinus the outer root-sheath. See Fig. 9. 
In these last two figures, which represent hair-follicles of 
the scalp of the dog, whose lymphatics had been injected 
with Berlin blue, it is seen with great distinctness that the 
injection material is contained not only in the lymphatic 
channels and spaces of the hair-sac and its surroundings, but 
that it penetrates also into the root-sheath. The injection 
material passes directly from the lymph-sinus around the 
root-sheath ¢nto the interstitial or cement substance between 
the epithelial cells, and what is still more remarkable and 
interesting, the injection material having penetrated up to 
the inner root-sheath accumulates there in @ distinct layer 
or space between this and the outer rootesheath and also 
between the former and the hair itself. It is very probable 
that it reaches this latter in the same way as the former, 
viz. through the cement substance of its (¢.e. the inner root- 
sheaths) scales. In the above case of the skin of the new- 
born child, whose lymphatics contained smaller and larger 
clumps of sebum, there existed most distinct signs of this 
latter substance being accumulated between the hair itself 
and the inner root-sheaths; further, between this and the 
outer root-sheath minute bright sebum particles were to be 
met with in the cement substance between the epithelial 
cells of the outer root-sheath, and were seen accumulated in 
the lymph-channels of the hair-sac. This is, then, clear 
evidence that the paths followed by the above Berlin-blue 
injection are the real ways of absorption, that is, are not 
produced artificially, since in the case of the sebum-absorp- 
