45 
IIL. 
MIMICRY, AND OTHER. PROTHOTIVE RE- 
SEMBLANCES AMONG ANIMALS. 
THERE is no more convincing proof of the truth of 
a comprehensive theory, than its power of absorbing 
and finding a place for new facts, and its capability 
of interpreting phenomena which had been previously 
looked upon as unaccountable anomalies. It is thus 
that the law of universal gravitation and the undu- 
latory theory of light have become established and 
imiversally accepted by men of science. Fact after 
fact has been brought forward as being apparently 
inconsistent with them, and one after another these 
very facts have been shown to be the consequences 
of the laws they were at first supposed to disprove. 
A false theory will never stand this test. Advancing 
knowledge brings to light whole groups of facts 
which it cannot deal with, and its advocates steadily 
decrease in numbers, notwithstanding the ability 
and scientific skill with which it may have been 
supported. The great name of Edward Forbes did 
not prevent his theory of “ Polarity in the distribu- 
tion of Organic beings in Time” from dying a 
natural death; but the most striking illustration of 
the behaviour of a false theory is to be found in the 
“Circular and Quinarian System” of classification: 
