THE TSETSE. 435 
the purpose of repelling these blood-thirsty insects which selected me for their victim, leaving 
my companions untouched. I have found the whole of the unprotected space round the neck 
covered with their bites, and my ears thickly stained with blood from the effects of their 
weapons. 
To this family belongs the terrible TsErsx, the curse of Southern Africa, which destroys 
horses, dogs, and cows 
by thousands, though it 
causes no harm to man 
or to any wild animal. 
Fortunately, it isa very 
local insect, its bound- 
aries being as sharply 
defined as if drawn on 
amap, one side of a 
stream being infested 
with this active insect, 
while the other is per- 
fectly free. The figure is 
drawn most accurately. 
The following account of its habits and the effects of its bite are given by Dr. Living- 
stone :—‘“‘In the ox the bite produces no more immediate effects than in man. It does not 
startle him as the gad-fly does ; but a few days afterwards the following symptoms supervene : 
the eyes and the nose begin to run; the coat stares as if the animal were cold ; a swelling 
appears under the jaw, and sometimes at the navel; and, though the animal continues to 
graze, emaciation commences, accompanied with a peculiar flaccidity of the muscles ; and this 
continues unchecked until, perhaps months afterwards, purging comes on, and the animal, no 
longer able to graze, perishes in a state of extreme exhaustion. Those which are in good con 
dition often perish soon after the bite is inflicted, with staggering and blindness, as if the 
brain were affected by it. Sudden changes of the temperature, produced by falls of rain, 
seem to hasten the progress of the complaint ; but, in general, the emaciation goes on uninter- 
ruptedly for months, and do what we will, the poor animals perish miserably. 
When opened, the cellular tissue on the surface of the body beneath the skin is seen to 
be injected with air, as if a quantity of soap-bubbles were scattered over it, or a dishonest, 
awkward butcher had been trying to make it look fat. The fat is of a greenish-yellow color, 
and of an oily consistence. All the muscles are so flabby, and the heart often so soft, 
that the fingers may be made to meet through it, and the lungs and liver partake of the 
disease. The stomach and bowels are pale and empty, and the gall-bladder is distended. 
with bile.” 
The insect which occasions these terrible results is hardly larger than a house-fly. It is 
curious that, although horses perish under its bite, mules, asses, and goats escape injury, and 
it seems that the bite of a single fly is sufficient to cause death. Another curious symptom is, 
that the blood loses its redness, and hardly stains the hands of the person who dissects the 
smitten animal. The source of all this mischief is to be found in a little poison-gland at 
the base of the mouth, not larger than a mustard-seed, and yet infinitely more deadly than 
the venom of the rattlesnake. The color of the Tsetse is brown, with a few yellow bars across 
the abdomen. When it bites a man, the pain which it causes is very slight, and the worst 
results are a trifling irritation not more severe than that caused by the bite of a gnat. 
A large insect is the BANDED Hornet-Fiy. It is an example of the Asilidee, among which 
are found the most gigantic specimens of the order. The body of these insects is long, and 
clothed with stiff hairs. They are fierce and voracious, feeding mostly upon other insects 
which they catch on the wing, and out of which they suck the vital fluids through their 
powerful proboscis. One species of this family has been known to capture and carry off a 
hive-bee, a remarkable instance of a stingless insect attacking and overcoming a creature so 
formidably armed as the bee. Some of them are said to attack cattle after the manner of 

YAv.Wh 
TSETSE.— Glossina morsitans. a, Head, with parts of the mouth. b, Antenna, or feeler. (The objects are 
differently magnified. The line underneath the figure of the Fly indicates the natural size of the Tsetse.) 
