BUSHBUCKS, KOODOOS, AND ELANDS 473 
cealing value whatever. They are probably gradually dis¬ 
appearing; they diminish the farther the animals are found 
from the probable original centre of development in the Middle 
African forests; and in the form farthest from this, the South 
African form, which has certainly been the last to be dif¬ 
ferentiated, the stripes have completely disappeared. This 
of course means that they have no concealing value such 
as to make them in even the slightest degree a factor 
in securing through natural selection the survival of the 
wearer under the conditions of the existing environment. 
The eland is certainly less plentiful than the other antelopes 
which possess a more advertising coloration; and it is more 
shy, and, instead of seeking to elude observation, prefers to 
station itself where it can detect its foes at a distance and 
run off. If the color of its coat were of benefit to it, it would 
certainly act so as to get that benefit, and this it never does. 
Evidently its coloration is an entirely negligible factor so far 
as its survival is concerned. 
The East African race differs very little from livingstonii 
of the Zambesi Valley. It may be distinguished usually by 
darker coloration and longer head, but the difference is 
merely an average affair. The race was based by Lydekker 
upon a specimen showing white chevrons on the snout and 
a narrow bush on the forehead. These characters are, how¬ 
ever, juvenile, and are as prevalent in the immature eland 
of Mashonaland as they are in British East Africa. The old 
males in East Africa have the entire forehead covered with 
a heavy mat of hair and lack the white chevrons bordering 
the mat on the snout, as do also the old males from the Zam¬ 
besi. Two bulls shot from the same herd on the Loita 
Plains by Colonel Roosevelt show both styles of coloration. 
The younger bull, which was a fully grown animal, had the 
narrow bush of hair on the forehead and white chevrons on 
the snout, while the aged bull of the same body size had the 
