E. M. CAMPBELL—OH" INSTIXCT. 
139 
shining on its right side, the sun would he on its left side if it 
returned by the same route before noon.^ 4 But this would still 
be the case if the ant kept on walking in the same direction, and 
passed its destination. In all probability, however, it would not 
have proceeded far on its homeward journey without recognising 
some landmark. Sir John shows also that ants are helped by sight 
in finding their way, and this prevents any conclusion as regards 
“the sense of direction” being drawn from the experiment in 
which they persistently took a short cut to their nest, from a place 
they had reached by a circuitous route.f Fabre has shown that a 
percentage of bees return home after removal to a certain distance, J 
but there is no reason why they should not be guided by actual 
observation. It is indeed difficult to see how “the sense of 
direction” could be otherwise than feebly developed in animals 
with a sustained power of flight, for when on the wing their range 
of vision is comparatively unimpeded, and would seem to be 
sufficient for their ordinary wants. They, like men living in 
civilised countries, have but little necessity for the use of this 
faculty. Pigeons have a great attachment to their home, but 
their success in “homing” is almost certainly due to observation 
and to sight. Before they are “flown” from a great distance 
they have to be trained stage by stage, so that they know the 
intermediate country. If a pigeon be tossed at night, or in a 
very thick fog, it will “not fly at all,” § and this could scarcely 
be the case if it knew its way. 
The course taken by migratory birds is frequently supposed to be 
governed by an inherited “ sense of direction.” The general 
statement that old and young birds of the same species do not 
migrate at the same time appears to support that view, but we do 
not know whether the young flight is not led by some old birds 
who are guided by landmarks: This suggestion cannot, however, 
account for long oceanic passages. Birds when flying have little 
or no shelter, and, unlike ourselves, have no artificial clothing. 
It is reasonable to suppose that they are more susceptible than 
we are to the atmospheric influences of different aspects, and they 
may by such means receive an indication of their course to a 
locality conducive to their well-being, both as to food and tempera¬ 
ture. Further observations may also show that the trans-oceanic 
flights of birds are largely influenced by the winds, which in the 
migratory periods of spring and autumn are more regular than 
at other seasons. When they have once touched land, they may 
wander until they reach a suitable habitat. I cannot help thinking 
that it is premature to discuss the perplexities of this question. 
* It must not be inferred from the above that I imagine the movement of the 
sun towards the west would necessarily invalidate the ant’s reckoning when 
steering for home. I should not be at all surprised to find it ascertained that 
bees, wasps, ants, and birds (if not most diurnal animals), could make approxi¬ 
mately accurate allowance for the gradual changing phenomena of light as 
occurring in the sun’s diurnal course. 
f l.c., p. 383. X ‘ Mental Evolution/ p. 293. 
§ 1 The Belgian Homing pigeon,’ p. 18. 
