﻿50 
  Mr. 
  H. 
  W. 
  Bates 
  on 
  the 
  Habits 
  

  

  two 
  genera 
  are 
  naturally 
  placed 
  in 
  close 
  vicinity 
  in 
  the 
  same 
  group 
  

   of 
  genera 
  of 
  Cicmdelides. 
  Relatively 
  to 
  the 
  Cicindelce, 
  the 
  former 
  

   have 
  a 
  body 
  more 
  robust, 
  a 
  broader 
  and 
  stronger 
  head 
  and 
  thorax, 
  

   with, 
  consequently, 
  stronger 
  mandibles, 
  showing 
  a 
  habit 
  of 
  preying 
  

   upon 
  larger 
  subjects, 
  and 
  greater 
  force 
  in 
  tearing 
  their 
  food 
  ; 
  their 
  

   antennas 
  are 
  longer 
  and 
  more 
  tapering, 
  showing 
  probably 
  an 
  

   acuter 
  sense, 
  whatever 
  that 
  sense 
  may 
  be 
  which 
  resides 
  in 
  those 
  

   organs. 
  Lastly, 
  their 
  legs 
  are 
  much 
  more 
  robust, 
  agreeing 
  with 
  

   their 
  terrestrial 
  habits. 
  They 
  may 
  be 
  defined 
  shortly 
  as 
  robust, 
  

   terrestrial 
  (cursorial), 
  and 
  nocturnal 
  Cicindelidce. 
  

  

  The 
  larvae 
  of 
  Megacephalce 
  inhabit 
  the 
  same 
  sandy 
  districts 
  as 
  

   the 
  perfect 
  insects, 
  in 
  cylindrical 
  burrows, 
  where 
  they 
  lie 
  in 
  wait 
  

   for 
  prey. 
  I 
  have 
  taken 
  two 
  or 
  three 
  species, 
  none 
  of 
  which 
  differ 
  

   in 
  any 
  essential 
  particular 
  from 
  the 
  descriptions 
  of 
  the 
  larva 
  of 
  

   Cicindelce. 
  The 
  head 
  is 
  broad, 
  semicircular, 
  concave 
  above 
  and 
  

   concave-convex 
  beneath, 
  with 
  the 
  mandibles 
  curved 
  upwards, 
  so 
  

   as 
  to 
  be 
  able 
  to 
  seize 
  anything 
  falling 
  on 
  the 
  concave 
  upper 
  surface 
  

   of 
  the 
  head. 
  They 
  are 
  so 
  rapacious 
  or 
  irascible, 
  seizing 
  anything 
  

   that 
  disturbs 
  them, 
  that 
  they 
  are 
  readily 
  taken 
  by 
  inserting 
  a 
  

   straw 
  in 
  their 
  burrows, 
  which 
  they 
  seize 
  instantly 
  and 
  retain 
  with 
  

   pertinacity. 
  

  

  Of 
  the 
  eleven 
  species 
  which 
  I 
  have 
  taken, 
  five 
  are 
  of 
  the 
  pale- 
  

   coloured 
  series 
  ; 
  five 
  of 
  the 
  brilliant-metallic 
  species, 
  copper- 
  

   coloured 
  green 
  or 
  blue, 
  all 
  with 
  an 
  ovate 
  pale 
  spot 
  at 
  the 
  apex 
  of 
  

   the 
  elytra 
  ; 
  and 
  one 
  is 
  obscure 
  black. 
  The 
  last-mentioned 
  (71/. 
  

   scpulchralis, 
  F.) 
  is 
  different 
  in 
  its 
  habits, 
  as 
  well 
  as 
  in 
  its 
  colour 
  

   and 
  form, 
  from, 
  the 
  other 
  two 
  groups. 
  It 
  is 
  found 
  in 
  dry 
  gravelly 
  

   places, 
  in 
  open 
  grassy 
  spaces 
  in 
  the 
  forest, 
  running 
  rather 
  slowly 
  

   about 
  the 
  roots 
  of 
  grass 
  in 
  the 
  daytime. 
  I 
  have 
  taken 
  it 
  only 
  at 
  

   the 
  Barra 
  of 
  the 
  Rio 
  Negro, 
  where 
  the 
  country 
  is 
  dry 
  and 
  undu- 
  

   lating, 
  and 
  the 
  forest 
  somewhat 
  low 
  and 
  thinned. 
  The 
  largest 
  

   of 
  the 
  pale 
  species, 
  about 
  an 
  inch 
  long, 
  is 
  the 
  robust 
  M. 
  testu- 
  

   dinea, 
  which 
  I 
  took 
  in 
  company 
  with 
  three 
  other 
  species 
  of 
  the 
  

   genus 
  on 
  the 
  sandy 
  shores 
  of 
  the 
  Teffe 
  at 
  Ega, 
  at 
  nigiit. 
  One 
  

   small, 
  smooth, 
  pale 
  species 
  (71/. 
  lani'inata, 
  Perty), 
  having 
  a 
  diamond- 
  

   shaped 
  dusky 
  spot 
  over 
  the 
  suture 
  of 
  the 
  elytra, 
  I 
  have 
  found 
  on 
  

   all 
  the 
  more 
  extensive 
  sandy 
  beaches, 
  more 
  or 
  less 
  sparingly, 
  from 
  

   Carefe, 
  near 
  Para, 
  to 
  Ega. 
  One 
  pale, 
  nearly 
  spotless 
  species 
  

   (71/. 
  cruciata), 
  9 
  lines 
  long, 
  I 
  took 
  only 
  at 
  the 
  Barra, 
  whence 
  I 
  

   sent 
  a 
  small 
  series 
  to 
  England. 
  Another 
  nearly 
  resembling 
  this 
  

   (71/. 
  blfasciata, 
  BruUe) 
  I 
  have 
  taken 
  more 
  abundantly 
  at 
  Ega 
  

   and 
  at 
  Santarem. 
  A 
  fifth 
  species 
  (71/. 
  asperula), 
  small, 
  and 
  

   covered 
  with 
  elevated 
  granulations, 
  I 
  took 
  only 
  two 
  specimens 
  of, 
  

   on 
  t!ie 
  sand 
  islands 
  in 
  mid-river, 
  on 
  the 
  Upper 
  Amazons. 
  In 
  the 
  

  

  