THE NATURALIST IX NICARAGUA. [Ch. I. 



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 it is only on account of the poverty of 

 our language that we have to speak of one species imi- 

 tating another, as if it were a conscious act. No such 

 idea is entertained, and it might have been well if some 

 new term had been adopted to express what is meant. 

 These deceptive resemblances are supposed, by the advo- 

 cates of the origin of species by natural selection, to have 

 been brought about by varieties of one species, that 

 somewhat resembled another having special means of 

 protection, being preserved from their enemies in conse- 

 quence 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, 

 that more and more closely approached the species imi- 

 tated, in form, colour, and movements, being protected. 

 These resemblances are not only between insects of diffe- 

 rent genera and orders, but between insects and flowers, 

 leaves, twigs, and bark of trees, and between insects and 

 inanimate nature/ They serve often for concealment, as 

 when leaves are imitated by leaf-insects and many but- 

 terflies ; or lor 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 Grey- 

 town Mr. Hollenbeck lent me his horse, and I rode a 

 few miles northward along the beach. On my return, I 

 tied up the horse and walked about a mile over the 



