﻿OF 
  THE 
  UNITED 
  STATES. 
  IT).") 
  

  

  rufo-bivittato, 
  elytris 
  testaccis, 
  striis 
  tcnuibus 
  vix 
  punctulatis, 
  interstitiis 
  planis, 
  dense 
  scabro-puncta- 
  

   tis, 
  abdomine, 
  prosterni 
  lobo, 
  thoracis 
  parte 
  inilcxa, 
  antennarum 
  articulo 
  I" 
  1 
  ", 
  pedibusque 
  testaceis 
  

   Long. 
  -28 
  — 
  -37. 
  

  

  Lake 
  Superior: 
  one 
  specimen 
  with 
  the 
  thorax 
  blackish 
  green, 
  and 
  two 
  with 
  a 
  broad 
  

   discoidai 
  reddish 
  yellow 
  vitta 
  each 
  side. 
  This 
  species 
  is 
  less 
  slender 
  than 
  A. 
  viridanus, 
  

   and 
  the 
  thorax 
  is 
  more 
  broadly 
  rounded 
  anteriorly, 
  so 
  that 
  it 
  appears 
  less 
  cylindrical. 
  

   The 
  postpectus 
  is 
  black. 
  

  

  A 
  specimen 
  found 
  with 
  those 
  just 
  mentioned 
  has 
  the 
  thorax 
  entirely 
  greenish 
  black, 
  

   above 
  and 
  beneath, 
  with 
  the 
  sides 
  much 
  more 
  straight, 
  converging 
  slightly 
  and 
  rounded 
  

   only 
  near 
  the 
  apex; 
  the 
  disc 
  is 
  punctured 
  as 
  in 
  this 
  species, 
  but 
  has 
  two 
  anterior 
  foveae 
  

   as 
  in 
  A. 
  viridanus; 
  the 
  abdomen, 
  like 
  the 
  pectus, 
  is 
  black, 
  and 
  docs 
  not 
  show 
  any 
  reddish 
  

   tinge. 
  This 
  may 
  be 
  a 
  distinct 
  species, 
  but 
  until 
  the 
  sexual 
  differences 
  are 
  better 
  under- 
  

   stood, 
  I 
  think 
  it 
  better 
  to 
  permit 
  it 
  to 
  remain 
  under 
  A. 
  incongrnus. 
  

  

  Ludius 
  Lair. 
  

  

  1. 
  L. 
  abruptus, 
  niger, 
  dense 
  punctatus, 
  fusco-subsericeus, 
  tarsis 
  piceis; 
  elytris 
  postice 
  obsolete 
  

   striatis, 
  ad 
  apicem 
  non 
  acuminatis. 
  Long. 
  "8. 
  

  

  JElater 
  abruptus 
  Say, 
  Ann. 
  Lye. 
  1, 
  253; 
  Trans. 
  Phil. 
  Soc. 
  6, 
  166. 
  

   Ludius 
  coracinus 
  Germ. 
  Zeitschr. 
  4, 
  47. 
  

  

  Middle, 
  Southern, 
  and 
  Western 
  States; 
  rare. 
  

  

  2. 
  L. 
  attenuatus, 
  obscure 
  piceo-sanguineus, 
  dense 
  punctatus, 
  fusco-subsericeus, 
  elytris 
  versus 
  

   apicem, 
  antennis, 
  pedibusque 
  nigris, 
  elytris 
  postice 
  vix 
  obsolete 
  striatis 
  apice 
  acuminatis. 
  Long. 
  -9. 
  

  

  JElater 
  attenuatus 
  Say, 
  Ann. 
  Lye. 
  1, 
  257; 
  Trans. 
  Am. 
  Phil. 
  Soc. 
  6, 
  16G. 
  

  

  Middle, 
  Southern, 
  and 
  Western 
  States; 
  more 
  abundant 
  than 
  the 
  preceding. 
  

  

  Dolopius 
  Esch. 
  

   Latreille 
  and 
  Germar 
  have 
  already 
  asserted 
  that 
  the 
  genera 
  Dolopius, 
  Agriotes, 
  and 
  

   Ectiuus, 
  of 
  Eschscholtz, 
  were 
  separated 
  on 
  evanescent 
  characters; 
  and 
  after 
  patiently 
  ex- 
  

   amining 
  our 
  native 
  species 
  I 
  have 
  adopted 
  their 
  opinion. 
  Differences 
  of 
  organic 
  character, 
  

   although 
  too 
  slight 
  for 
  generic 
  distinction, 
  are 
  readily 
  found, 
  and 
  enable 
  us 
  to 
  facilitate 
  the 
  

   determination 
  of 
  the 
  species, 
  which 
  may 
  be 
  grouped 
  as 
  follows: 
  

  

  A. 
  Mandibulre 
  perpendiculariter 
  dilatatse, 
  apice 
  emarginatrc 
  

  

  B. 
  Mandibulae 
  apice 
  compress;!?, 
  non 
  dilatatse: 
  

  

  1. 
  Antennse 
  articulis 
  2 
  et 
  3, 
  4 
  to 
  coniunctis 
  nequalibus 
  

  

  2. 
  Antennre 
  articulis 
  2 
  et 
  3, 
  4 
  to 
  singulis 
  vix 
  brevioribus. 
  

  

  * 
  Laminre 
  coxarumintus 
  vix 
  latiores, 
  (thoracis 
  margine 
  plus 
  minus 
  obso- 
  

   leto:) 
  ------- 
  

  

  ** 
  Laminoe 
  coxarum 
  intus 
  subito 
  paulo 
  dilatatse, 
  (thoracis 
  margine 
  in- 
  

   tcgro:) 
  -------- 
  

  

  A. 
  

  

  1. 
  D. 
  mancus, 
  crassiusculus, 
  ater, 
  vel 
  piceus, 
  pubescens, 
  capite 
  thoraceque 
  confertim 
  sat 
  grosse 
  

  

  VOL. 
  X. 
  — 
  i.) 
  

  

  