THE SKIN. 197 



tection. Carpenter says, " What has been termed the rete 

 mucosum is simply the last-formed portion of the cuticle." 



463. The various coloring of this inner layer of the cuti- 

 cle gives to some animals their varied hues to the serpent, 

 the frog, and the lizard, and some fishes, which have a splen- 

 dor of hue almost equal to polished metal. Goldfish and the 

 dolphin owe their difference of color, and the brilliancy of 

 their hues, to the color of this layer of skin. 



464. Underneath the cuticle is the true* skirt, (Fig. XXVL 

 6, &,) the seat of all the active functions of the cutaneous mem- 

 brane. This layer is a dense and thick membrane, and com- 

 posed of firm and strong fibres, that are interwoven like the felt 

 of a hat. It is almost filled with minute blood-vessels, so many 

 that a large proportion of the blood of the whole system flows 

 in them. If we cut the outer skin, no -blood flows, be- 

 cause no blood is there; but if we cut through that and 

 into the inner skin, we cannot fail to wound some of these 

 vessels. 



465. In health, when every thing goes on well in the ani- 

 mal body, the blood is properly distributed in all the organs, 

 and each receives its due proportion; then it flows freely 

 through the vessels of the skin, and the surface is florid and 

 the cheek is rosy. But cold contracts the cutaneous vessels, 

 and lessens their capacity for blood. The cutaneous circu- 

 lation is sometimes influenced even by the state of the mind 

 and the affections: the blood flows more abundantly in the 

 capillaries of the face when the modest youth blushes, or 

 when one is excited ; and it is easily driven away, and the 

 cheek turns pale, when one is oppressed with fear, or is over- 

 come with anxiety. 



466. This skin is furnished with a great quantity of 

 nerves, for it is endowed with an exquisite degree of sensi- 

 bility to pleasure and to pain ; and it is also the seat of the 

 sense of touch. In man, the nerves are more abundantly dis- 

 tributed to the skin than to the other organs. But those 

 animals which are covered with hair, feathers, or scales, have 



