Reasoning in Ants 25 
faculty in these ants. I once saw a wide column trying to 
pass along a crumbling, nearly perpendicular, slope. They 
would have got very slowly over it, and many of them would 
have fallen, but a number having secured their hold, and 
reaching to each other, remained stationary, and over them 
the main column passed. Another time they were crossing 
a water-course along a small branch, not thicker than a 
goose-quill. They widened this natural bridge to three 
times its width by a number of ants clinging to it and to 
each other on each side, over which the column passed three 
or four deep. Except for this expedient they would have 
had to pass over in single file, and treble the time would have 
been consumed. Can it not be contended that such insects 
are able to determine by reasoning powers which is the best 
way of doing a thing, and that their actions are guided by 
thought and reflection? This view is much strengthened 
by the fact that the cerebral ganglia in ants are more de- 
veloped than in any other insect, and that in all the Hymen- 
optera, at the head of which they stand, “ they are many 
times larger than in the less intelligent orders, such as 
peetiesy’ 1, 
The Hymenoptera standing at the head of the Articulata, 
and the Mammalia at the head of the Vertebrata, it is curious 
to mark how, in geological history, the appearance and 
development of these two orders (culminating, one in the 
Ants; the other in the Primates) run parallel. The Hymen- 
optera and the Mammalia both make their first appearance 
early in the secondary period, and it is not until the com- 
mencement of the tertiary epoch that ants and monkeys 
appear upon the scene. There the parallel ends. No one 
species of ant has attained any great superiority above all its 
fellows, whilst man is very far in advance of all the other 
Primates. 
When we see these intelligent insects dwelling together 
in orderly communities of many thousands of individuals, 
their social instincts developed to a high degree of perfection, 
making their marches with the regularity of disciplined 
troops, showing ingenuity in the crossing of difficult places, 
assisting each other in danger, defending their nests at the 
risk of their own lives, communicating information rapidly 
1 Darwin, Descent of Man, vol, i. p. 145. 
