9074 Insects. 
brain of the bee or that of the hen having laboured in their con- 
struction. 
My own observation of the habits of insects and the knowledge 
J have acquired from that of other naturalists, have irresistibly led me 
to the adoption of very opposite opinions. If those I have quoted 
above hold good as regards the wasp and bee, they must equally apply 
to all the recorded economies of the insect world. I will mention two 
or three instances of what I call insect sagacity, exhibiting skill, 
reflection, contrivance, &c. —in fact, a number of those qualifications 
which are usually summed up in the one debateable sense called 
instinct. 
A little swarm of Trigonz are on the wing; they are in search of 
some hollow tree or other suitable cavity adapted for their hive ; a tree 
with a large hollow in the trunk is found; this hollow is some inches 
in diameter, as well as in length. Such a house is not adapted to 
their purpose; it requires, in fact, the front of the domicile built, and 
of course a doorway constructed: had this swarm flown twenty yards 
further a tree with a suitable hollow and also a suitable entrance would 
have been found. Although the tree selected is not ready for their 
purposes it matters little, the bees can by contrivance make it so; 
accordingly they collect a quantity of moist clay and build up the wall, 
leaving a suitable opening for their entrance and exit. Will it be 
argued that this is parallel to the formation of the calcareous covering 
of the egg in the body of the hen? Is no amount of intelligence 
exhibited in all this contrivance, and in the choice of a material so 
admirably adapted for the purpose required ? 
Let us now look in another direction. There is an army of the 
travelling ant on the march: onward they go, over hill and level 
plain, and down into the deep ravine ; but they halt suddenly, a narrow 
stream intercepts their progress: they do not turn aside, such is not 
their wont, the difficulty must be surmounted. A low bush grows close 
to the margin of the stream; one of its branches overhangs the water ; 
an ant is seen ascending the bush and traversing the overhanging 
branch to its furthest extremity: having reached this, it seizes the 
twig with its jaws, and suspends itself by them over the stream; 
another ant follows, and attaching itself to the legs of the first, hangs 
down likewise; this example is followed by others, until a chain of 
ants hangs over the stream; this is wafted to and fro until the ant at 
the extremity touches and clings to some twig or blade of grass on the 
opposite side: a suspension bridge is thus formed, and over this the 
whole army passes. Should no bush be found suitable for their pur-. 
