Fig. 113.
Fig. 113. 1, 1, The cuticle. 2, 2, The colored layer of the cuticle. 3, 3, The papillary layer, exhibiting the nerves as they form loops. 4, 4, The net-work of nerves. 5, 5, The true skin. 6, 6, 6, Three nerves that divide to form the net-work (4, 4.) 7, 7, 7, The furrows between the papillæ. 8, 8, 8, Three papillæ magnified fifty diameters.
629. The LYMPHATICS are found in great numbers in the true skin, and they are so minute that they cannot be seen with the naked eye; but when these hair-like vessels are injected with quicksilver, (a work of great difficulty,) the surface injected 288 resembles a sheet of silver. In this way their existence can be imperfectly demonstrated. They are a part of the vascular net-work situated upon the upper surface of the true skin. Each papilla is supplied with a lymphatic filament, the mouth of which opens beneath, and lies in contact with the under surface of the cuticle. This net-work of vessels communicates through the open meshes of the true skin with larger lymphatic trunks, that open into the venous system.
628. How are the nerves of the small papillæ arranged? How in the large papillæ? What does fig. 113 represent? 629. What is said of the cutaneous lymphatics? How is their existence proved?
Fig. 114.
Fig. 114. A plexus of lymphatic vessels in the skin, considerably magnified from an injected preparation.