﻿368 
  Mr. 
  C. 
  J. 
  Gahan 
  on 
  mimetic 
  resemblances 
  

  

  black 
  ; 
  the 
  prothorax 
  is 
  yellowish 
  tawny 
  ; 
  the 
  elytra, 
  in 
  

   typical 
  examples, 
  have 
  a 
  shining 
  brownish 
  black 
  colour, 
  

   and 
  each 
  is 
  marked 
  with 
  five 
  rounded 
  tawny 
  spots 
  arranged 
  

   in 
  the 
  order 
  2,2,1. 
  The 
  femora 
  are 
  fulvous, 
  the 
  tibiae 
  and 
  

   tarsi 
  black. 
  A 
  repetition 
  of 
  these 
  details 
  would 
  almost 
  

   exactly 
  describe 
  the 
  coloration 
  and 
  style 
  of 
  marking 
  of 
  

   Lema 
  Batesii, 
  Baly, 
  a 
  species 
  from 
  the 
  same 
  regions. 
  In 
  

   this 
  species, 
  however, 
  the 
  two 
  middle 
  spots 
  of 
  each 
  elytron 
  

   are 
  usually 
  united 
  to 
  form 
  a 
  sort 
  of 
  transverse 
  band. 
  

  

  In 
  one 
  variety 
  of 
  D. 
  10-guttata 
  nearly 
  all 
  the 
  black 
  

   colour 
  is 
  obliterated 
  from 
  the 
  basal 
  three-fourths 
  of 
  the 
  

   elytra 
  ; 
  the 
  apical 
  spot 
  on 
  each 
  remains 
  surrounded 
  by 
  a 
  

   somewhat 
  irregular 
  black 
  border. 
  This 
  variety 
  occurs 
  in 
  

   Ecuador 
  and 
  the 
  Upper 
  Amazons, 
  and 
  has 
  its 
  counterfeit 
  

   in 
  a 
  species 
  of 
  Lema 
  {L. 
  oculata, 
  Lac), 
  also 
  from 
  Ecuador. 
  

  

  Lema 
  nigrovittata, 
  Guer., 
  found 
  in 
  Mexico 
  and 
  North 
  

   America, 
  has 
  the 
  elytra 
  striped 
  with 
  black 
  and 
  yellow 
  in 
  

   close 
  imitation 
  of 
  Diabrotica 
  vittata, 
  Fab., 
  which 
  is 
  very 
  

   common 
  in 
  the 
  same 
  localities. 
  

  

  Other 
  striped 
  species 
  of 
  the 
  two 
  genera 
  are 
  very 
  much 
  

   alike. 
  The 
  most 
  remarkable, 
  perhaps, 
  are 
  the 
  Mexican 
  

   species, 
  L. 
  bisbivittata, 
  Clark, 
  and 
  D. 
  Fairmairei, 
  Baly. 
  

   They 
  are 
  of 
  about 
  the 
  same 
  size. 
  The 
  pale 
  yellow 
  

   stripes 
  of 
  their 
  elytra 
  correspond 
  almost 
  exactly 
  in 
  

   position 
  and 
  in 
  width. 
  The 
  elytra 
  have 
  in 
  each 
  species 
  

   the 
  same 
  peculiar 
  violet-brown 
  ground 
  colour, 
  and 
  they 
  are, 
  

   moreover, 
  raised 
  into 
  narrow 
  longitudinal 
  costee 
  between 
  

   the 
  rows 
  of 
  punctures 
  with 
  which 
  they 
  are 
  impressed. 
  

   So 
  that 
  in 
  colour, 
  sculpture, 
  and 
  pattern 
  of 
  marking 
  the 
  

   elytra 
  in 
  the 
  two 
  species 
  offer 
  a 
  strong 
  resemblance. 
  

  

  It 
  is 
  not 
  often 
  that 
  two 
  species 
  of 
  different 
  genera 
  are 
  

   more 
  deceptively 
  alike 
  than 
  L. 
  dimidiaticornis, 
  de 
  Borre, 
  

   and 
  D. 
  lepida, 
  Say. 
  These 
  are 
  also 
  found 
  in 
  Mexico. 
  

   The 
  head 
  and 
  prothorax 
  in 
  both 
  are 
  of 
  the 
  same 
  reddish 
  

   colour. 
  In 
  D. 
  lepida 
  the 
  elytra 
  are 
  glossy 
  black, 
  and 
  

   each 
  is 
  marked 
  with 
  two 
  confluent 
  ivory-like 
  spots 
  near 
  

   the 
  middle, 
  with 
  a 
  similar 
  spot 
  near 
  the 
  apex. 
  In 
  L. 
  

   dimidiaticornis 
  the 
  elytra 
  have 
  a 
  glossy 
  bluish 
  black 
  

   colour, 
  and 
  are 
  each 
  marked 
  with 
  a 
  transverse 
  yellowish 
  

   band 
  at 
  the 
  middle, 
  and 
  with 
  a 
  spot 
  of 
  the 
  same 
  colour 
  

   near 
  the 
  aj)ex. 
  The 
  transverse 
  band 
  is 
  often 
  slightly 
  

   constricted 
  in 
  its 
  middle, 
  so 
  that 
  it 
  comes 
  more 
  closely 
  

   to 
  resemble 
  the 
  two 
  confluent 
  spots 
  occupj'ing 
  a 
  similar 
  

   position 
  in 
  the 
  Diabrotica. 
  

  

  