388 DR, E. KLEIN. 
as I find that there are lymphatics with valves in all layers 
of the skin. 
18. Continuing the horizontal sections below the sub- 
cutaneous tissue, z.e. into the adipose tissue, we find that 
the connective-tissue septa between the lobules of the latter, 
which in the new-born child are very well marked and 
regulary arranged, contain very numerous lymphatics; these 
in well-injected specimens appear as plexuses of densely 
placed vessels and clefts, situated between the lamellz con- 
stituting those septa. They will be later on described as the 
interlobular lymphatics of the adipose tissue. The vessels 
are smaller than those of the. subcutaneous tissue, and they 
pass into the plexus of large lymphatics situated underneath 
the adipose tissue. 
19. A very interesting observation that I made in the skin 
of a child that had died during, or very soon after birth, was 
this :—The skin was covered, as usual, with a thick layer of 
the secretion of the sebaceous glands, but in vertical and 
horizontal sections through the hardened skin lymphatic 
vessels in all different layers could be seen, containing in 
their interior small and large clumps of what was undoubtedly 
the same sebum as that on the free surface. In the large 
lymphatics of the depth this was especially very easily 
ascertained. 
We shall presently have to return to this fact, and it will 
then become clear how this sebum found its way into the 
lymphatics, and of how great importance this is in the 
understanding of the absorption from the external surface 
by the lymphatics of the skin. At present we wish to point 
out that the mouths of the hair-follicles were greatly dis- 
tended by, and filled with this sebum. 
20. The lymphatics of the skin of the dog are similar in 
their arrangement to those of man, and for this reason we 
shall be able to be brief in their description, especially since 
we can refer the reader to the figures 1, 2, 3, 5 of the 
Plates accompanying this report. These illustrations and 
their explanation printed at the end of this paper give an 
accurate and sufficiently clear idea of the distribution and 
nature of these lymphatics. It will be thus seen that the 
lymphatics, even of the most superficial layer (Fig. 2), are 
large vessels, some of which present all appearances asso- 
ciated with valves in lymphatics, viz. saccular dilatations 
and corresponding constrictions. ‘The vessels of this super- 
ficial layer are very densely placed, and therefore of short 
extension. Owing tothe arrangement of the hairs in groups 
of four to six or more hair-follicles of unequal thickness, 
