IN VERTEBRATES 59 
striped “blazer” of the Wasp, and the spotted jacket of the 
Lady-Bird. Unless very hard pressed by hunger it appears 
that the foes of animals so coloured and marked give them a 
wide berth. But without careful observation and experiment 
it would remain an open question whether this resulted from 
Instinct or Intelligence, or a mixture of the two. The cases 
which have so far been properly investigated appear to prove 
that Intelligence here comes into play, and that a young animal 
has to learn from experience that some things are good to eat 
and others not. The thorough and long-continued researches 
of Lloyd Morgan upon artificially - hatched chicks definitely 
prove that they at least have to acquire such useful knowledge 
for themselves. He thus describes (in Animal Behaviour) how 
some of his chicks learnt that alternate bands of black and 
orange, as possessed by the caterpillars of the Cinnabar Moth, 
are associated with disagreeable sensations:—‘“ The following 
experiment was made with young chicks. Stripes of orange and 
black paper were pasted beneath glass slips, and on them meal 
moistened with quinine was placed. On other plain slips meal 
moistened with water was provided. The young birds soon 
learnt to avoid the bitter meal, and then would not touch plain 
meal if it was offered on the banded slip. And these birds, 
save in two instances, refused to touch cinnabar caterpillars, 
which were new to their experience. They did not, like other 
birds, have to learn by particular trials that these caterpillars are 
unpleasant. Their experience had already been gained through 
the banded glass slips; or so it seemed. I have also found that 
young birds who had learnt to avoid cinnabar caterpillars left 
wasps untouched.” 
Nest-BurLpinc 1n Birps.—There can be no reasonable doubt 
that in its main features the nest-building of birds is a matter of 
instinct. One of the best proofs of this is afforded by cases 
where individuals kept in captivity from the time of hatching, 
under conditions which excluded the possibility of instruction or 
imitation, have nevertheless constructed nests of the kind proper 
to their species. Further experiments, however, are much to be 
desired, especially on birds which indulge in architecture of such 
characteristic kind as to be quite unmistakable. It would, of 
course, be necessary to make the nesting conditions in such cases 
as natural as possible. Other instincts, tending to the benefit 
