﻿478 
  PROCEEDINGS 
  OF 
  THE 
  NATIONAL 
  MUSEUM. 
  vol. 
  xx. 
  

  

  CHLAMYS 
  PLICATA 
  Fabricius. 
  

  

  Chlamys 
  pJlcaia 
  Faijricius, 
  Ent. 
  Sye. 
  Snpp., 
  p. 
  111. 
  — 
  Olivikr, 
  Ent., 
  VT, 
  p. 
  876, 
  

   pi. 
  I, 
  fig. 
  o 
  a-b. 
  — 
  Lacokpaire, 
  Moh., 
  \). 
  701. 
  — 
  Crotch, 
  Proc. 
  Phil. 
  Acad. 
  

   Sci., 
  XXY, 
  p. 
  ?,0. 
  

  

  After 
  separating' 
  the 
  preceding 
  forms 
  specifically 
  there 
  still 
  remains 
  

   G. 
  plicata, 
  a 
  species 
  very 
  variable 
  in 
  scnlpture. 
  The 
  thorax 
  is 
  strigose 
  

   over 
  the 
  whole 
  surface 
  and 
  the 
  tubercles 
  on 
  the 
  sides 
  of 
  the 
  disk 
  are 
  

   obsolete 
  and 
  without 
  coarse 
  punctures; 
  the 
  central 
  gibbosity 
  has 
  never 
  

   any 
  punctures 
  on 
  its 
  posterior 
  surface, 
  but 
  the 
  anterior 
  face 
  and 
  the 
  

   crest 
  are 
  variable, 
  being 
  impunctate 
  or 
  having 
  smaller 
  shallow 
  foveje. 
  

   These 
  latter, 
  however, 
  are 
  never 
  coarse 
  and 
  confluent; 
  the 
  summit 
  is 
  

   more 
  or 
  less 
  bifid 
  and 
  tlie 
  longitudinal 
  channel 
  i.s 
  obsolete 
  or 
  impressed. 
  

   The 
  elytral 
  sculpture 
  is 
  still 
  more 
  variable, 
  but 
  the 
  tubercles 
  are 
  never 
  

   as 
  large 
  and 
  as 
  acutely 
  ridged 
  as 
  in 
  C. 
  memnonia. 
  The 
  tubercle 
  on 
  

   the 
  basal 
  lobe 
  is 
  always 
  distinct 
  and 
  isolated, 
  but 
  varies 
  in 
  size; 
  the 
  

   juxta-scutellar 
  andpost-scutellar 
  tubercles 
  are 
  often 
  entirely 
  absent 
  and 
  

   when 
  i)resent 
  are 
  isolated, 
  and 
  never 
  connected 
  with 
  the 
  median 
  ridge. 
  

   The 
  small 
  spiny 
  ridge 
  along 
  the 
  sutural 
  edge 
  at 
  the 
  base, 
  nearly 
  always 
  

   present 
  in 
  C. 
  menmoniaj 
  is 
  here 
  totally 
  wanting, 
  and 
  the 
  surface 
  is 
  flat. 
  

   The 
  tubercles 
  of 
  the 
  humero-median 
  range 
  are 
  either 
  isolated 
  or 
  con- 
  

   nected 
  in 
  an 
  undulating 
  ridge, 
  but 
  are 
  never 
  connected 
  with 
  the 
  basal 
  

   or 
  scutellar 
  tubercles; 
  the 
  lateral 
  carina 
  is 
  seldom 
  entire, 
  generally 
  

   broken 
  up, 
  and 
  the 
  anterior 
  part 
  is 
  often 
  developed 
  transversely; 
  the 
  

   posterior 
  tubercles 
  are 
  more 
  or 
  less 
  developed; 
  the 
  intervals 
  between 
  

   the 
  tubercles 
  are 
  uniform, 
  never 
  showing 
  any 
  velvety 
  foveje, 
  always 
  

   sparsely 
  punctate, 
  either 
  flat 
  or 
  covered 
  with 
  numerous 
  smaller 
  tuber- 
  

   cles. 
  The 
  pygidiuni 
  has 
  a 
  median 
  carina 
  and 
  a 
  fovea 
  each 
  side 
  at 
  apex; 
  

   the 
  balance 
  of 
  the 
  surface 
  varies 
  from 
  flat 
  to 
  coarsely 
  reticulate. 
  

  

  By 
  a 
  careful 
  study 
  of 
  the 
  characters 
  used 
  for 
  separating 
  C. 
  asshnilis 
  

   King, 
  and 
  C. 
  jyolycocca 
  Lacordaire, 
  I 
  have 
  been 
  unable 
  to 
  find 
  even 
  local 
  

   races 
  where 
  they 
  are 
  at 
  all 
  constant. 
  Both 
  are 
  said 
  to 
  differ 
  from 
  G. 
  

   pUcata 
  in 
  having 
  impunctate, 
  obsoletely 
  canaliculate 
  gibbosity 
  of 
  the 
  

   thorax 
  and 
  the 
  lateral 
  carina 
  of 
  the 
  elytra 
  are 
  divided; 
  G. 
  polycocci 
  

   should 
  difler 
  from 
  G. 
  assimilis 
  in 
  the 
  more 
  isolated 
  elytral 
  tubercles. 
  

  

  Specimens 
  from 
  the 
  Middle 
  and 
  Northern 
  States 
  agree 
  best 
  with 
  the 
  

   descriptions 
  of 
  these 
  two 
  forms, 
  and 
  the 
  more 
  roughly 
  sculptured 
  indi- 
  

   viduals 
  from 
  Florida 
  and 
  Texas 
  should 
  be 
  the 
  true 
  G.pUcata.^ 
  but 
  I 
  

   have 
  seen 
  occasional 
  female 
  specimens 
  from 
  Xew 
  York 
  or 
  the 
  District 
  

   of 
  Columbia 
  as 
  rough 
  as 
  any 
  from 
  the 
  farthest 
  South 
  and 
  vice 
  versa, 
  

   smoother 
  specimens 
  from 
  Texas 
  and 
  Florida. 
  Moreover, 
  the 
  charac- 
  

   ters 
  used 
  lor 
  their 
  separation 
  are 
  very 
  rarely 
  combined 
  in 
  any 
  one 
  

   individual. 
  Consequently 
  I 
  am 
  forced 
  to 
  consider 
  G. 
  polycocca 
  and 
  

   G. 
  assiniilis 
  as 
  merely 
  synonyms 
  of 
  plicata 
  and 
  not 
  even 
  entitled 
  to 
  

   rank 
  as 
  races. 
  

  

  