410 
SAVAGE SUDAN 
projection which entirely prevents its seeing straight ahead— 
indeed in life, when these projections are enfolded in thick 
hide, its view in that direction would be intercepted up to an 
angle of, say, 45 degrees. In the common black rhinoceros 
(R. bicornis) the projection, though present, is less pronounced, 
and would not prevent the beast from seeing almost straight 
ahead. 
[It remains to record the melancholy fact that, within a few 
days after revising the proofs of the above, my friend and 
neighbour Mr Sydney Pearson passed away—on May 30th, 
1920. His death at the age of sixty was, moreover, directly 
attributable to the hardships undergone during the expedition 
here described: those befouled “water-holes” of Bahr-el- 
Ghazal introduced the germs of what proved a fatal disease. 
Such is the toll that Africa exacts from her devotees, even the 
strongest. Personally I owed Pearson a deep debt of grati¬ 
tude : for once, when on the threshold of undertaking a big 
expedition (alone), an attack of fever precluded my completing 
its final organisation. Pearson (though fully engaged on 
similar preparations for himself) at once took the business in 
hand and, on my recovering, I found every detail—to the last 
pin—prepared and ready for a start. A./.P.] 
B 
COLOUR-PROTECTION 
Considered Chiefly in Relation to Wild Beasts 
and Birds of the Sudan 
That the Almighty should have so created and clothed His 
creatures as not only to conceal the harmless from possible 
enemies, but also to render the predatory less visible to their 
allotted prey, is a theory so fascinating as at first sight to 
captivate the imagination. Therein lies the danger of theories. 
This one, certainly, all who love the study of Nature thirstily 
drank in. But not all proceeded to put its tenets to the test 
and corroboration of field-observation. 
Those who did so at once began to detect inherent fallacies; 
and later to wonder if, by some confusion of thought, another 
