364 APPENDIX. 
accompanying my original description, was afterwards copied upon 
the titlepage of Dr. Livingstone's Travels (without acknowledgment), 
and in my memoir I ventured to suggest not only that the Tsetse 
was identical with the Zimb of Bruce, but also possibly with the 
Tsaltsalya ; and further, that " the fly that is in the uttermost part 
of the rivers of Egypt," described by the prophet Isaiah (ch. vii. 18, 
19), and considered as the cause of one of the plagues of Egypt, 
may also have been no other than the Tsetse. Two notes recently 
published on this insect, with suggestions of remedying or preventing 
its attacks, may be added : — 
Lewis Hornor, in the "Times," 25th February 1879, writes, " Having 
hunted in the African fly country and seen many horses and oxen die 
of the bite, against which no external application is, I firmly believe, 
any safeguard, I venture to call attention to the precautions adopted 
by the Boer elephant hunters in the interior. The Tsetse inhabits 
narrow and clearly defined strips of country, familiar to all natives, 
and readily evident to strangers. On approaching one of these 'fly 
belts ' (so called) a halt is made, and inspanning again at sundown 
the Boer treks through at night in safety. I only remember one case 
of mishap, when, in crossing a belt near the confluence of the Chobe 
and Zambesi, two or three oxen out of nearly forty were bitten, and 
that, if my memory serves me, on a bright moonlight night." 
The African traveller Hildebrandt recommends strongly, in the 
" Korrespondenzblatt der afrik. Gesellschaft," the use of petroleum for 
those travelling in the tropics, as a protection against insects. Occa- 
sional applications to the face and hands ensured entire freedom 
from mosquitoes, and the same method sufficed to preserve horses and 
cattle against the deadly attacks of the Dondorobo gadfly, which so 
often cripples the movements of the explorer. Petroleum likewise 
protected the Natural History Collections of the traveller from ants, 
moths, etc. 
[The description of Plates E — H is given on p. 365.] 
