THE THICK CUTIS VERA. 



425 



horizontal layers a superficial and a deep one the vertical 

 connection between the two being found only at comparatively 

 rare intervals. 1 Renaut regards the skin as a lymphatic sponge, 

 the minutest ramification being but the space between the bun- 

 dles of fibres ; the coarser differing from these in having an 

 endothelial lining (connective-tissue cells ?), there being in 

 neither case a true wall, which is found only in the lymphatic 

 vessels of the subcutaneous tissue. 2 Vertical sections taken 

 from the specimens of skin injected by puncture, showed a 

 similar, but not so complete an injection, as was effected by 



FIG. 181. Injected lymph-system magnified about eight diameters : a, epidermis; /, cutis vera; ff, 

 adipose tissue ; h, hair. 



the present method. The latter seems to possess special ad- 

 vantage, as a larger lymph surface is exposed at one time. 



Fig. 181 shows the route taken by the Berlin blue, which, as 

 will be seen, ascends in nearly vertical columns through the 

 fat-canals to the base of the hair-follicles, going round the 

 sides of the sweat-gland. When a slight amount only had 

 passed into the canal, a medium power of the microscope 

 showed the blue lying in and staining the tissue accom- 

 panying the ascending blood-vessel in the so-called "perivas- 

 cular space." The lateral clefts were filled with the mass, 



1 Zur Kenntniss der Lymphgefasse der Haut, von Isidor Neumann. 



2 Renaut. Op. cit. 



