MUSCULAR ACTION AND DIRECTION OF HAIR 65 



he would have observed in his own splendid frontal region and 

 brows excellent examples of the phenomena which form the subject 

 of this chapter. This I know, though I never saw him in the flesh, 

 for it so happens that in the great volume published in the jubilee 

 of The Origin, and called Darwin and Modern Science, two good 

 photographs of him, at the ages of thirty -five and about seventy-one 

 are reproduced. These both show, but the later one much more 

 clearly, good examples of these long and not very ornamental 

 aberrant hairs. Thirty -five years of arduous thought and work 

 had told their tale on him and twisted from their normal paths the 

 lengthening thickening hairs of his eyebrows. 



Also, if he had looked a little beyond the eyebrows he would 

 have seen some very deep wrinkles of the skin on his forehead and 

 round his orbits. It is these two groups of facts, wrinkles and 

 twisted, changed hairs of man's eyebrows, which give the answer 

 to the question " Can muscular action change the direction of hair 

 in the individual ? " 



In 1903 I drew the attention of the Anatomical Society of 

 Great Britain and Ireland to these two groups of facts under the 

 title " Notes on the Eyebrows of Man," and presented some large 

 drawings of individual elderly men of my acquaintance, and the 

 present chapter is only an extension of that little piece of work. 



No area of the mammalian skin is so useful and easy to follow 

 as this in answering the present question, for though the previous 

 chapter supplied part of the answer in a very fruitful field, the proof 

 still remained one of " tremendous probability " and not more. 

 But in the frontal and superciliary region of man there is complete 

 proof of the truth of the affirmative answer, as I shall show. 



Here again we must encounter our old friend the normal slope 

 of hair. As I stated in 1903, " The normal arrangement of the hair 

 on the eyebrows of a moderately hairy subject is as follows : in 

 the middle line the hairs of the two sides tend to meet and form a 

 somewhat confused group of hairs ; passing away from the middle 

 line the hairs assume a nearly sagittal direction, then become 

 more sloped away, and a sharp change in the direction of the 

 frontal and orbital streams brings the remaining hairs into that 

 regular accurate arrangement of a united stream so characteristic 

 of a hairy subject, and this passes along the superciliary ridge 

 to the external angular process " — all of which can be seen at a 

 glance by any one who looks closely enough, as with the eyes of a 

 lover, for example, at the brows of a dark-haired maid or youth. 

 In the young these hairs lie close to the skin, and with that very 

 interesting group of persons we have no more to do here, except 



