THE WATERBUCK 127 
rather warmer-coloured pelage, with more marked facial 
adornments. 
The waterbuck of the South, Ellypsiprymnus, has 
not lent itself to any vexing colour-variations. Defassa, 
in the reverse, varies considerably. Its vagaries, however, 
are chiefly limited to colour-distinctions, and these alone 
(whatever may be their value, if any, in Nature’s scheme) 
never constitute a safe basis for differentiation. Personally, 
I attach little importance to them ; nevertheless colour- 
distinctions constitute the main reason for spinning this 
yarn! It was because we encountered in the Sudan, 
waterbuck totally different in colour only from any 
of the thousands I must have seen in South and East 
Africa, as well as in the Sudan itself, that this chapter has 
materialised. That may seem an example of preaching 
what you don’t practise—probably it is ; but the incident 
is worth telling of itself, so here it goes into print! 
The Sobat River (530 miles south of Khartoum), by 
reason of its erratic bends and generally eastward trend, 
presents great difficulties to navigation by sail. We 
were, however, anxious to explore a tributary of the 
Sobat, the Khor Filus ; and by dint of much hard work— 
alternately sailing, poling, and laboriously dragging by 
tow-rope from the bush-clad bank—we reached that goal. 
Landing next morning and advancing up the Khor— 
which was little more than a semi-stagnant backwater 
abounding in exotic bird-life-—Lowe and I were soon 
joined by a friendly native or two; but presently our 
escort expanded into an ever-increasing mob of savages of 
the wildest and most weird aspects. These were Shilluks, 
tall, lean, and muscular, varying apparently between six 
and seven feet in stature. All were stark naked, some 
smeared red, others ochre-yellow, or a ghastly ash-grey, 
almost white; and with odd clay-cemented coiffures. 
Each carried three spears, and all were most friendly 
and loquacious, gesticulating anent Gamoos—Abu Uruff 
— tdtel, etc. Having no fancy for hunting in a mob, we 
