40 
PROTECTIVE AND WARNING COLOURATION 
IN ANIMALS. 
(Wirn Lantern Views). 
By Dr. JAS. H. ASHWORTH, D.Sc. 29th March, 1904. 

The President, Mr. W. L. Grant, mentioned with gratification 
that Dr. Ashworth, now the Demonstrator of Zoology in the 
University of Edinburgh, was an old school boy at the Carlton 
Road School, and had built well upon the foundations which 
were laid in that school, and so long as there were such scholars, 
who, like Dr. Ashworth, were pursuing an honourable and useful 
career, the memory and good name of that school would not 
perish. (Cheers.) 
The Lecturer, who had a cordial reception, discoursed 
pleasantly for over an hour on the parts played by nature in 
the colouring of animals and insects. Not only were animals 
coloured for protection, so as to enable them to escape their 
natural enemies and avoid being eaten, but the colours also 
played the part of warnings to other animals. The colouring 
was said to be general when the colour of an animal harmonised 
with the effect of its surroundings to escape the notice of its 
enemies. Among this class were the zebras, of which curious 
instances of deception were related by Drummond in his essay 
on mimicry. In the class of special resemblances came certain 
caterpillars which resembled the twigs of the plant on which 
they fed. For hours they remained during the day motionless, 
and did their feeding at night when their enemies, the birds, 
were asleep. The birds were deceived by the resemblance of the 
caterpillar to the twig of the tree. The green lizard did not 
notice the larva so long as it was still, but as soon as it moved it 
would be devoured. There was a case on record of an 
entomologist of thirteen years standing taking his scissors to cut 
off the twig from a plum tree, but as he was about to do so, the 
supposed twig turned out to be only larve. The caterpillars 
contained fluid under pressure, and this accounted for the 
cylindrical shape of their bodies. 
