eB The Naturalist in Nicaragua 
beetles I found a curious longicorn (Desmiphora fasciculata), 
covered with long brown and black hairs, and closely resem- 
bling some of the short, thick, hairy caterpillars that are 
common on the bushes. Other closely allied species hide 
under fallen branches and logs, but this one clung exposed 
amongst the leaves, its antennz concealed against its body, 
and its resemblance to a caterpillar so great, that I was at 
first deceived by it. It is well known that insectivorous 
birds will not touch a hairy caterpillar, and this is only one 
of numberless instances where insects, that have some 
special protection against their enemies, are closely imitated 
by others belonging to different genera, and even different 
orders. Thus, wasps and stinging ants have hosts of 
imitators amongst moths, beetles, and bugs, and I shall 
have many curious facts to relate concerning these mimetic 
resemblances. To those not acquainted with Mr. Bates’s 
admirable remarks on mimetic forms, I must explain that 
we have to speak of one species imitating another, as if it 
were a conscious act, only on account of the poverty of our 
language. No such idea is entertained, and it would have 
been well if some new term had been adopted to express 
what is meant. These deceptive resemblances are supposed, 
by the advocates of the origin of species by natural selection, 
to have been brought about by varieties of one species some- 
what resembling another having special means of protection, 
and preserved from their enemies in consequence of that 
unconscious imitation. The resemblance, which was perhaps 
at first only remote, is supposed to have been increased in the 
course of ages by the varieties being protected that more and 
more closely approached the species imitated, in form, colour, 
and movements. These resemblances are not only between 
insects of different genera and orders, but between insects 
and flowers, leaves, twigs, and bark of trees, and between 
insects and inanimate nature. They serve often for conceal- 
ment, as when leaves are imitated by leaf-insects and many 
butterflies, or for a disguise that enables predatory species to 
get within ‘reach of their prey, as in those spiders that resemble 
the petals of flowers amongst which they hide. 
That I may not travel over the same ground twice, I may 
here mention that on a subsequent visit to Greytown I rode 
a few miles northward along the beach. On my return, I 
