ETHNOLOGY. 289 
indicate Mongolian affinities are the yellow as opposed to 
the black colour of the skin, the prominence of the cheek 
bones, and the supposed obliquity of the opening of the 
eyelids. This last peculiarity, as Fritsch {Die Eittgeborene 
Sud-Afrika's, p. 286) has shown, is due simply to the 
disagreeable necessity of keeping the eyelids constantly 
half-closed, owing to the glare and, as others have pointed 
out, the sandflies, to which these homeless savages are 
self-exposed. The Swiss Professor, Schiess-Gemuscus, of 
Basle, has similarly explained the causation of snow- 
blindness (see ArcJiiv. fiir Ophthahnologie, xxv. 3, p. 173), 
by reference to the blepharospasmus and conjunctivitis, 
produced by the dryness and the glare of the upland 
snowfield ; and I apprehend that the osseous structures 
underlying the organs protecting the eye may be reason- 
ably supposed to undergo some modification in correlation 
with the increased demand for work, which " blepharo- 
spasmus " expresses as being thrown upon the muscular 
structures which they support. Thus the prominent malar 
arch and the forwardly projecting outer segments of the 
orbit, as seen alike in the Mongolian of the treeless steppe, 
in the Eskimo of the snow-desert, and the Bushman of the 
sun-burnt South African uplands, may receive a physio- 
logical as opposed to a morphological explanation. But, 
when we come further to consider the structure and compo- 
sition of the various segments of the orbital ring in these 
races, we find combined with this physiologically explicable 
similarity a very considerable morphological difference. 
This is constituted by the conformation of the nasals, 
which in the Bushman form invariably an all but level 
plane between the nasal processes of the maxillaries, and 
contribute, being narrow, but a small factor to the interocular 
space, which, when the soft parts are in sitti, appears dis- 
proportionately wide as compared with the same area in 
other races. In Mongols, Eskimos, and Australians the 
nasals very ordinarily form a more or less elevated arch, 
and they are not by any means so narrow as they are 
almost always in the Bushman race. In this latter these 
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