﻿62 
  Mr. 
  J. 
  O. 
  Westvvood 
  on 
  the 
  

  

  teeth, 
  and 
  the 
  left 
  one 
  in 
  both 
  sexes 
  has 
  the 
  first 
  and 
  third 
  large, 
  with 
  

   a 
  small 
  one 
  between 
  them; 
  the 
  labial 
  palpi 
  are 
  remarkably 
  long, 
  

   the 
  antennte 
  pale 
  luteous, 
  with 
  the 
  first 
  four 
  joints 
  more 
  or 
  less 
  

   marked 
  with 
  black 
  on 
  the 
  upper 
  side. 
  The 
  pronotum 
  is 
  nearly 
  

   smooth 
  above, 
  with 
  two 
  transverse 
  punctured 
  impressions, 
  the 
  

   ordinary 
  longitudinal 
  one 
  only 
  slightly 
  impressed, 
  the 
  portion 
  

   behind 
  the 
  second 
  transverse 
  impression 
  is 
  black. 
  The 
  elytra 
  

   are 
  broader 
  behind 
  the 
  middle, 
  and 
  covered 
  with 
  extremely 
  

   numerous 
  and 
  very 
  minute 
  conical 
  granulations, 
  those 
  of 
  the 
  disc 
  

   being 
  the 
  largest, 
  the 
  points 
  of 
  which 
  are 
  directed 
  backwards; 
  

   at 
  about 
  one-third 
  of 
  the 
  width 
  of 
  the 
  elytra, 
  on 
  each 
  side 
  of 
  the 
  

   suture, 
  is 
  an 
  irregular 
  row 
  of 
  deeper 
  punctures, 
  forming 
  an 
  in- 
  

   distinct 
  longitudinally 
  impressed 
  striola 
  on 
  each 
  elytron 
  ; 
  beyond 
  

   the 
  middle, 
  and 
  towards 
  the 
  side, 
  is 
  a 
  somewhat 
  oval 
  black 
  spot, 
  

   its 
  inner 
  margin 
  oblique, 
  and 
  produced 
  behind 
  into 
  a 
  small, 
  slender, 
  

   curved 
  mark^ 
  directed 
  towards 
  the 
  suture, 
  beyond 
  which 
  the 
  elytra 
  

   are 
  pale 
  luteous, 
  as 
  well 
  as 
  at 
  the 
  sides. 
  The 
  whole 
  of 
  the 
  under- 
  

   side 
  of 
  the 
  body, 
  palpi 
  and 
  legs 
  are 
  luteous, 
  the 
  four 
  posterior 
  

   femora 
  having 
  a 
  black 
  spot 
  near 
  the 
  tip 
  on 
  the 
  upper 
  side. 
  

  

  Long. 
  corp. 
  5 
  lin. 
  I-^-L- 
  

  

  Having 
  no 
  typical 
  specimen 
  of 
  M. 
  iestudinea 
  for 
  comparison, 
  it 
  

   is 
  not 
  possible 
  to 
  decide 
  with 
  certainty 
  whether 
  Mr. 
  Bates' 
  spe- 
  

   cimens 
  are 
  specifically 
  distinct 
  from 
  that 
  species, 
  several 
  of 
  the 
  

   characters 
  mentioned 
  above 
  being 
  omitted 
  in 
  Dr. 
  King's 
  de- 
  

   scription. 
  

  

  Sp. 
  3. 
  Megacephala 
  laminata, 
  Perty, 
  Del. 
  An. 
  art. 
  Bras. 
  1, 
  p. 
  2, 
  

   pi. 
  1, 
  f. 
  3. 
  

   M. 
  nocturna, 
  Klug, 
  MS., 
  Dej., 
  Sp. 
  Gen. 
  v. 
  p. 
  203. 
  

  

  Sp, 
  4. 
  Megacephala 
  bifasciala, 
  BruUe 
  in 
  D'Orbigny, 
  Voy. 
  Amer. 
  

   merid. 
  VI. 
  ii. 
  p. 
  1, 
  pi. 
  1, 
  f. 
  1. 
  

   M. 
  cequinoxialis, 
  Fabr., 
  Dej., 
  &c., 
  but 
  not 
  of 
  Linnaeus, 
  

   which 
  = 
  Brach'tnus 
  complanatus, 
  F. 
  

   Dr. 
  Erichson, 
  Jahrbucher 
  Entomol. 
  1837, 
  n. 
  209, 
  considers 
  that 
  

   the 
  name 
  il/. 
  cequinoxialis 
  should, 
  however, 
  be 
  retained, 
  as 
  having 
  

   been 
  used 
  by 
  Fabricius 
  in 
  a 
  genus 
  far 
  removed 
  from 
  Brachimis 
  ; 
  

   but 
  it 
  is 
  quite 
  evident, 
  from 
  the 
  words 
  of 
  Fabricius, 
  Syst. 
  Eleuth. 
  

   i. 
  p. 
  243, 
  n. 
  60, 
  " 
  Species 
  mihi 
  obscura," 
  that 
  he 
  had 
  never 
  seen 
  

   it, 
  but 
  had 
  merely 
  taken 
  it 
  up 
  from 
  the 
  writings 
  of 
  Linnaeus. 
  

  

  According 
  to 
  M. 
  D'Orbigny 
  this 
  species 
  rests, 
  during 
  the 
  day, 
  

   at 
  the 
  bottom 
  of 
  holes, 
  which 
  it 
  burrows 
  in 
  the 
  margins 
  of 
  rivers, 
  

   coming 
  abroad 
  only 
  on 
  the 
  approach 
  of 
  night, 
  and 
  running 
  with 
  

   extreme 
  velocity. 
  

  

  