pase PROTECTIVE RESEMBLANCES AMONG ANIMALS 77 
in other cases, with the addition of a few that are peculiar to 
it. The most obvious is, that we have gradations of mimicry 
and of protective resemblance—a fact which is strongly 
suggestive of a natural process having been at work. Another 
very serious objection is, that as mimicry has been shown to 
be useful only to those species and groups which are rare and 
probably dying out, and would cease to have any effect should 
the proportionate abundance of the two species be reversed, 
it follows that on the special-creation theory the one species 
must have been created plentiful, the other rare; and, not- 
withstanding the many causes that continually tend to alter 
the proportions of species, these two species must have always 
been specially maintained at their respective proportions, or 
the very purpose for which they each received their peculiar 
characteristics would have completely failed. A third diffi- 
culty is, that although it is very easy to understand how 
mimicry may be brought about by variation and the survival 
of the fittest, it seems a very strange thing for a Creator to 
protect an animal by making it imitate another, when the 
very assumption of a Creator implies his power to create it 
so as to require no such circuitous protection. These appear 
to be fatal objections to the application of the special-creation 
theory to this particular case. 
The other two supposed explanations, which may be 
shortly expressed as the theories of “similar conditions” and 
of “heredity,” agree in making mimicry, where it exists, an 
adventitious circumstance not necessarily connected with the 
well-being of the mimicking species. But several of the most 
striking and most constant facts which have been adduced 
directly contradict both these hypotheses. The law that 
mimicry is confined to a few groups only is one of these, for 
“similar conditions” must act more or less on all groups in a 
limited region, and “heredity” must influence all groups 
related to each other in an equal degree. Again, the general 
fact that those species which mimic others are rare, while 
those which are imitated are abundant, is in no way explained 
by either of these theories, any more than is the frequent 
occurrence of some papable mode of protection in the imitated 
species. ‘Reversion to an ancestral type” no way explains 
why the imitator and the imitated always inhabit the very 
