PERSONAL APPEARANCES IN HEALTH AND DISEASE. 8 1 



before pointed out, it is probable that all pigment owes 

 its primary origin to the colouring matter of the red 

 blood corpuscles, yet variations in degree of pigmenta- 

 tion of parts are not necessarily associated with any 

 marked change in the blood itself. It will be remem- 

 bered also that the colour of the skin depends upon two 

 factors, the chief being that of the blood circulating 

 in the deep layers, that gives the " flesh-tint " which 

 artists aim so strenuously to reproduce in all its delicate 

 and varied hues a colour too, the intensity and delicacy 

 of which must largely depend on thickness of cuticle ; 

 and the other being the presence of pigment in the 

 cuticle a very varying condition, but one which in- 

 fluences largely the predominant colour, and which, if 

 in excess, as in the negro, will suffice to completely 

 disguise the flesh-tint. However, even in the negro there 

 are still regions which show the blood colour, e.g., the 

 mucous membranes ; and observation of the colour of the 

 lips, of the nails, or of the conjunctiva of the eye, will 

 reveal more accurately than any change that may be 

 noticed in the skin, the change that has taken place in 

 the vascular regions beneath. 



The difference in colour produced by difference in the 

 quantity of blood in a part may be shown by a very simple 

 experiment. If one hand be held above the head whilst 

 the other is allowed to hang down by the side for a few 



