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off, and do not again quit the nest. In addition to the ordinary 
workers, there is in some species a second, or rather a third, form of 
female. 'In almost any ants’ nest we may see that the workers differ 
more or less in size. 
The food of ants consists of insects, great numbers of which 
they destroy; of honey, honey-dew, and fruit—indeed, scarcely any 
animal or sweet substances comes amiss to them. Some species—such, 
for instance, as the small brown garden ant—ascend bushes in search 
of aphids, which are called the ants’ cows. The ant then taps the 
aphis gently with her antennae, and the aphis emits a drop of sweet 
fluid which the ant drinks. Sometimes the ants even build covered 
ways up to and over the cows, which they protect from other insects. 
It is a curious fact that in some parts of the world ants are eaten 
and regarded as great delicacies. The Siamese particularly are noted 
as placing ants eaten with red pepper or curried on their menus. They 
also serve them rolled in green leaves with shreds of pork. 
Another curious fact is that formic acid was first made from ants. 
They were either placed on a cloth and hot water poured over them, 
this water afterward containing the acid, or the ants were placed in a 
retort of glass with water and the retort heated. The vapor distilled 
over contained formic acid. 
Locusts.—While they do not attack mankind, yet the locusts are 
perhaps the most serious pest that the African farmer has to contend 
with. This insect, shaped much like the familiar grasshopper, often 
appears in great swarms, devouring every twig, green shoot, leaf and 
bud, in addition to whole fields of grain. They cover the ground so 
thickly that it is said that the footprints made by a horse among them 
are filled up in a few seconds. In 1798 South Africa for a space of 
two thousand square miles was completely covered with them. 
It is only fair to the locust to state, however, that the native 
reciprocates for the destruction of his crops by eating the locust in 
turn. Their method is to gather great quantities of live locusts, place 
them in ovens previously heated by a very hot fire, cover them up and 
leave them to bake. The next process is to spread them out in the 
sun to dry, taking care that the other locusts do not eat them. When 
thoroughly dried, the process taking two or three days, the locusts are 
ground up into a powder with which a sort of pudding is made. 
