256 THE HUMAN SKIN. 



are the infinitesimals, the immense field of touch and take — the basis 

 of the pyramid of the senses. 



But the necessity that sent us from the fat to the corium, and 

 from the corium to the papillae, pushes us onwards to demand fur- 

 ther instruments. The papillae depending for their exquisite life 

 upon the most delicate sensibility, upon pleasures and pains so fine 

 that our senses give scarcely an idea of them, must not be exposed 

 directly to the rude breath of the outer world, which would cause 

 them agony, and soon blunt them to the delights of touch. The 

 papillae therefore cannot be the last covering. What is nature's next 

 resource ? The blunter sensations are themselves assumed by the 

 superaddition of new layers ; not however actively sensitive layers, 

 but beds of organization that less feel themselves, than regulate the 

 feelings of the skin. These coarser touches become the matrix and 

 defence of the finer. The layer covering in the papillae must of 

 course be soft and yielding, or it would be as injurious to the parts 

 beneath as external objects themselves ; at least when contact with 

 the outer world is taking place. This layer is the rete mucosum, 

 or mucous network of the old anatomists. 



It is a soft, tenacious substance, placed upon and between the 

 conical papillae, and furnishes a bed that groups them together, and 

 into which they protrude. When carefully peeled off, and viewed 

 by the microscope against the light, it assumes the appearance of a 

 network, which is caused by the counter-sinking whereby it fits to 

 the uneven surface of the papillae ; the thin places seeming like 

 holes. Possibly also some of the papillae perforate it. This layer 

 is the seat of the color of the skin both in the European and other 

 races, and what is remarkable, the coloring matter is chiefly abun- 

 dant in its inner parts, and decreases outwards ; though sometimes 

 dark points continue to the surface, and form little streamlets of 

 blackness as far as the exterior integument. 



The unfinished softness of the rete, necessary for fostering the 

 papillae, unfits it for contact with tangible objects, which would 

 lacerate it at the first touch ; and consequently nature (in which 

 utility is creative), not only compresses and hardens the rete in its 

 superficial parts, but superadds to it a fine covering termed the 

 cuticle, a kind of glazy platework, capable of assuming, at the bid- 



