Volume 1

The student's book of cutaneous medicine and diseases of the skin / by Erasmus Wilson.

  • Wilson, Erasmus, Sir, 1809-1884.
Date:
1864
Catalogue details

Licence: Public Domain Mark

Credit: The student's book of cutaneous medicine and diseases of the skin / by Erasmus Wilson. Source: Wellcome Collection.

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    whicli, in its deepest part, forms a strong network, with oval or circular meslies : the strands or fasciculi of the net- work being of about half the breadth of the arese. In proceeding outwards, we find that the network becomes finer, both in respect of the fasciculi and of the meshes; and, as we approach the surface, assumes the character of a fine but dense spongy tissue. The large meshes of the under surface of the derma are filled with fatty tissue, and give passage to the blood-vessels which supply the surface of the skin, and also to the lymphatic vessels and cutaneous nerves; and the finer arese of the superficial portion support the ultimate ramifications of the vessels and nerves, together with the capillary and nervous plexuses. ^Looking to the constituents of its structure, the derma is a compound tissue, consisting of a framework of white fibrous tissue, with which muscular tissue, and yeUow elastic tissue, are intermingled; and supporting and main- taining in its areolar spaces, fatty tissue, together with arteries, veins, capHlary vessels, lymphatics, nerves, and, as we shaU see further on, hair-foUicles and glands. The average tHckness of the derma is half a line ; on the back of the trunk it measures in depth about three-fourths of a line ] while on the heel the measvirement is more than aline, and sometimes as much as a line and a half. Viewing the two surfaces of the derma,—the superficial and the deep, there appears a very manifest difference between them ; the latter a coarse and firm network of white fasciculi and large open spaces, with a scanty supply of vessels and nerves ; the former a fine spongy tissue, seemiuc- to be made up almost wholly of capillary vessels and minute nerves, and bristling on the surface with mi- nute, semi-transparent, finger-like papHte. This difference between its deeper and its superficial part has caused a distinction to be made between them, wHch is expressed by the terms pars reticularis and pm-s papiUa^'is, or papiUarj^ layer The distinction is arbitrary: there is no line ot