16 
Pigmentation, Susceptibility and Race Selection 
derived from the sympathetic system: these cell groups are derived from the 
ectoderm. It would seem that in general there is some close connection between 
pigmentation and the ectoderm, and although pigment is found in certain meso- 
blastic structures, such as the choroid and stroma of the iris in the eye, the cells of 
the perilymphatic spaces in the internal ear and the cortex of the suprarenal body, 
yet even these are closely associated with the ectoderm, and it might ultimately be 
found that the pigmented cells are ectodermal in origin. The case of complete 
albinism already referred to is open to this interpretation; certainly the majority of 
these normally pigment-containing structures are ectodermal in origin, and it might 
be concluded that the ectodermal derivatives are the chief pigment-producing 
structures in the body. Tocher's findings regarding the relation of pigmentation 
to insanity suggest an etiological association in this connection, the hair and brain 
both being ectodermal structures. 
From general observation it must be concluded that there is some association 
between the colour of the hair and the type of skin in the individual. The fresh 
complexion, easily freckled, met with in red-haired, and the olive and more sallow 
skin occurring in dark-haired persons, are well known. If we have this association 
between the colour of the hair and the skin, one of the chief excretory organs of 
the body, it might reasonably be expected that some definite relationship could be 
found between pigmentation and the ability to withstand disease. Beddoe found 
that, in his experience as a physician, on the whole, dark-complexioned children 
showed more tenacity of life than fair ones*. 
The same author remarksf that pale shades in the hair, and in the eyes also, 
are the results of a defect of secretion, but that it does not necessarily follow that 
they are a mark of weakness. Several facts, however, might point in that direc- 
tion, such as the physical and constitutional inferiority of albinos, the comparative 
lightness of the hair of children and the changes which take place in disease, 
generally in the direction of dullness and paleness of hue. 
Brown! ee J found that the Jewish children in Glasgow exhibited a considerable 
susceptibility to scarlet fever and diphtheria, associated with a high degree of 
recuperative power. 
Ripley§, commenting on the large proportion of dark-haired and dark-eyed 
persons in the continental towns, states that it is not improbable that there is in 
the dark hair and eye some indication of vital superiority, for it requires energy 
and courage, physical as well as mental, not only to break the ties of home, 
but also to maintain one's self afterwards under the stress of city life. After 
discussing the defects of sense in albinos he goes on to say that these facts 
tend to justify the conclusion that pigmentation, if not absolutely necessary, 
at least conduces to acuteness of sense, and that when abundantly present is often 
* Beddoe : The Races of Britain, p. 223. 
+ Beddoe : Ibid., p. 224. 
% Brown lee : Report of the City of Glasgow Fever and Smallpox Hospitals, Behndere, 1906. 
§ Kipley : The Races of Europe, p. 557. 
