38 
ANIMAL INTELLIGENCE. 
was passing along it, he turned it round, so that end b was 
at c, and c at b. 6 In most cases the ant immediately 
turned round also ; but even if she went on to b or c, as 
the case might be, as soon as she came to the end of the 
bridge she turned round.’ Next, between the nest and 
the food he placed a hat-box twelve inches in diameter 
and seven inches high, cutting two small holes, so that 
the ants in passing from the nest to the food had to pass 
in at one hole and out at the other. The box was fixed 
upon a central pivot, so as to admit of being rotated easily 
without much friction or disturbance. When the ants had 
well learnt their way, the box was turned half round as 
soon as an ant had entered it, 6 but in every case the 
ant turned too, thus retaining her direction . 5 Lastly, 
Sir John took a disk of white paper, which he placed 
in the stead of the hat-box between the nest and the 
food. When an ant was on the disk making towards 
the food, he gently drew the disk to the other side of the 
food, so that the ant was conveyed by the moving surface 
in the same direction as that in which she was going, but 
beyond the point to which she intended to go. Under 
these circumstances 4 the ant did not turn round, but went 
on 5 to the further edge of the disk, when she seemed 6 a 
good deal surprised at finding where she was . 5 
These experiments seem to show that the mysterious 
‘ sense of direction , 5 and consequent faculty of 6 homing,' 
are in ants, at all events, due to a process of registering, 
and, where desirable, immediately counteracting any change 
of direction, even when such change is gently made by a 
wholly closed chamber in which the animal is moving, and 
not by any muscular movements of the animal itself. And 
the fact that drawing the moving surface along in the 
same direction of advance as that which the insect is 
pursuing does not affect the movements of the latter, 
seems conclusively to show that the power of registration 
has reference only to lateral movements of the travelling 
surface ; it has no reference to variations in the velocity 
of advance along the line in which the animal is pro- 
gressing . 1 
1 While this MS. is passing through the press Sir John Lubbock has 
