PROTECTIVE COLOURING AND MIMICRY, 387 



of great scarcity ; that is, few examples of each species occur in 

 the places where they are found, and they constitute groups which 

 are remarkable for the strongly marked diversity and limited 

 ranges of their species." 



I took a beautiful weevil Heilipus trachypterus (Germ.) in 

 Minas, whose cream-coloured and black elytra, studded with 

 rugosities or tubercles, resemble the lichens of the tree trunks. 

 I also found some sand-beetles, which were protectively coloured. 

 Many other beetles, which would not be considered to be thus 

 guarded against their foes, are found to be so in their native 

 haunts, from resembling either a black dead leaf or a berry, etc. 



I may also mention the grasshoppers. Some long and thin, 

 exactly simulating blades of grass ; others larger, some two inches 

 long by half an inch thick. One specimen that I have is Steirodon 

 citrifolium (Serv.). These are exactly similar to green leaves. 

 There is also the curious group of Phasmidse, or stick-insects. 

 For further details I would refer to Mr. A. R. Wallace's book, 

 " Tropical Nature ; " also to a very interesting essay on " Protective 

 Resemblances and Mimicry in Insects," by Roland Trimen, F.R.S., 

 in the February and March numbers of the Entomologist for 1885 ; 

 also a paper on " The Habits of the Butterflies of the Amazon 

 Valley," by A. R. Wallace.* 



There is no doubt that insects are endowed with protective 

 colouring and mimicry to assist those which are edible in avoiding 

 their innumerable foes, while the gaudily coloured genera may 

 freely display themselves, as, being unpalatable, they have no need 

 of concealment. 



The theory of these phenomena has been so frequently dis- 

 cussed that I must do no more than allude to the subject ; but 

 I am compelled to confess that I cannot agree with the hypothesis 

 of the gradual development of such protection ; not only because 

 I fail to comprehend how, during the necessarily lengthened period 

 when such an advantageous condition was being produced, the 

 individuals could derive any benefit, but also especially on 

 account of the dangerous deductions that have been drawn from 

 the theory of evolution. 



It is unnecessary to detail all the/r0 and con arguments which 

 * " Trans. Entom. Soc.," 1853. 



