If PROTECTIVE RESEMBLANCES AMONG ANIMALS 55 
to butterflies or to bees, of beetles to wasps, and of locusts to 
beetles, has been many times noticed by eminent writers ; 
but scarcely ever till within the last few years does it appear 
to have been considered that these resemblances had any 
special purpose, or were of any direct benefit to the insects 
themselves. In this respect they were looked upon as 
accidental, as instances of the “curious analogies” in nature 
which must be wondered at but which could not be explained. 
Recently, however, these instances have been greatly multi- 
plied ; the nature of the resemblances has been more carefully 
studied, and it has been found that they are often carried out 
into such details as almost to imply a purpose of deceiving 
the observer. The phenomena, moreover, have been shown 
to follow certain definite laws, which again all indicate their 
dependence on the more general law of the “survival of the 
fittest,” or, “the preservation of favoured races in the struggle 
for life.” It will, perhaps, be as well here to state what these 
laws or general conclusions are, and then to give some account 
of the facts which support them. 
The first law is, that in an overwhelming majority of cases 
of mimicry, the animals (or the groups) which resemble each 
other inhabit the same country, the same district, and in 
most cases are to be found together on the very same spot. 
The second law is, that these resemblances are not indis- 
criminate, but are limited to certain groups, which in every 
case are abundant in species and individuals, and can often 
be ascertained to have some special protection. 
The third law is, that the species which resemble or 
“mimic” these dominant groups are comparatively less 
abundant in individuals, and are often very rare. 
These laws will be found to hold good in all the cases of 
true mimicry among various classes of animals to which we 
have now to call the attention of our readers. 
Mimicry among Lepidoptera 
As it is among butterflies that instances of mimicry are 
most numerous and most striking, an account of some of the 
more prominent examples in this group will first be given. 
There is in South America an extensive family of these 
insects, the Heliconide, which are in many respects very 
