162 
PRESIDENT S ADDRESS. 
has been brought under my notice during the last few weeks 
by a gentleman now collecting in the Andes of Columbia in 
South America. He says that one of the commonest reptiles 
in the district in which he has been collecting is a small 
poisonous coral Snake most remarkably coloured, viz., 
white with black rings, a purple red head and purple red tip 
to the tail. In a retired valley in this district while collecting 
insects he found on a broad-leaved plant a Caterpillar of 
one of the Geometridece or looper Moths, about three centi- 
metres in length, which was marked and coloured exactly 
in the same way as the Snake — white with black wings, 
red head and tail. He said the likeness was so striking 
that when he first saw it he could hardly believe his eyes. 
Whether the Caterpillar was really poisonous I know not ; 
but it was evidently adopting the same advertisement as 
the Snake. 
In South America there are two groups of Butterflies, both 
protected by being distasteful, and both very numerous both 
in species and in individuals, and these so closely resemble 
each other that it is difficult even for practised entomologists 
to distinguish them ; they are also mimicked by a great many 
other Butterflies, some of which are. and some are not, 
protected. 
The two great protected groups of Butterflies of the New 
World are the Ithomiidce, which are related to the Danaidce 
of the Old World, and the Helicomdce , which are peculiar 
to the New World. In both these families the insects exude 
a juice which has an offensive smell and renders them dis- 
agreeable to the creatures which would feed upon them. 
Now insects belonging to these two groups resemble each 
other and afford the most perfect examples of mimicry 
known. They are both protected, but according to the 
Mullerian theory, they have both assumed the same dress 
in order that the loss of life occasioned by the teaching of 
inexperienced enemies may be divided between two, or in 
