﻿406 
  REVISION 
  OF 
  THE 
  ELATERID.K 
  

  

  Several 
  of 
  these 
  artificial 
  groups 
  were 
  elaborated 
  by 
  the 
  editor, 
  in 
  the 
  five 
  volumes 
  of 
  

   the 
  work 
  just 
  mentioned, 
  while 
  Erichson 
  lent 
  his 
  assistance 
  by 
  monographing 
  those 
  with 
  

   serrate 
  ungues, 
  and 
  those 
  with 
  truncate 
  prostcrnal 
  spine. 
  

  

  A 
  number 
  of 
  artificial 
  genera 
  have 
  been 
  constructed 
  by 
  various 
  entomologists, 
  who, 
  

   however, 
  with 
  the 
  exception 
  of 
  Kirby, 
  in 
  the 
  Fauna 
  Boreali 
  Americana, 
  have 
  not 
  suggested 
  

   any 
  ideas 
  respecting 
  the 
  classification 
  of 
  the 
  species.* 
  

  

  The 
  genera 
  found 
  in 
  Austria 
  have 
  been 
  carefully 
  described 
  by 
  Redtenbacher 
  in 
  his 
  

   Fauna 
  Austriaca, 
  but 
  unfortunately 
  with 
  the 
  tendency 
  to 
  adopt 
  the 
  large 
  number 
  of 
  

   genera 
  founded 
  by 
  Eschscholtz 
  on 
  unimportant 
  characters. 
  

  

  The 
  group 
  of 
  Eucnemides 
  has 
  been 
  revised 
  as 
  a 
  separate 
  family, 
  by 
  Mr. 
  Guerin, 
  in 
  

   the 
  Annales 
  de 
  la 
  Societe 
  Entomologique 
  de 
  France, 
  (ser. 
  2d., 
  vol. 
  1,) 
  where 
  numerous 
  very 
  

   gross 
  errors 
  of 
  Mr. 
  Laporte 
  arc 
  corrected. 
  

  

  More 
  recently, 
  Mr. 
  Sober, 
  in 
  the 
  fauna 
  of 
  Chili 
  by 
  Claudio 
  Gay, 
  has 
  described 
  a 
  

   large 
  number 
  of 
  South 
  American 
  species, 
  which 
  he 
  has 
  distributed 
  into 
  a 
  large 
  number 
  of 
  

   new 
  genera 
  founded 
  upon 
  the 
  form 
  of 
  the 
  mandibles, 
  mentum, 
  and 
  the 
  proportions 
  of 
  the 
  

   joints 
  of 
  the 
  antenna?. 
  As 
  no 
  reference 
  is 
  made 
  to 
  the 
  labours 
  of 
  previous 
  investigators, 
  

   and 
  as 
  care 
  is 
  taken 
  to 
  avoid 
  all 
  mention 
  of 
  the 
  parts 
  of 
  the 
  body, 
  which 
  served 
  as 
  the 
  

   basis 
  of 
  earlier 
  classifications, 
  the 
  result 
  of 
  this 
  has 
  been 
  to 
  produce 
  confusion, 
  which 
  can 
  

   only 
  be 
  removed 
  by 
  the 
  comparison 
  of 
  the 
  actual 
  types 
  of 
  the 
  genera 
  established 
  by 
  

   Mr. 
  Sober 
  with 
  those 
  already 
  known. 
  I 
  may 
  also 
  add, 
  from 
  the 
  study 
  of 
  our 
  native 
  

   species, 
  that 
  the 
  characters 
  upon 
  which 
  Mr. 
  Solier 
  relies, 
  especially 
  those 
  derived 
  

   from 
  the 
  form 
  of 
  the 
  mandibles, 
  are 
  difficult 
  to 
  perceive, 
  and 
  when 
  perceived 
  are 
  of 
  no 
  

   value, 
  since 
  they 
  vary 
  in 
  species 
  which 
  are 
  certainly 
  closely 
  allied. 
  I 
  am 
  happy 
  to 
  con- 
  

   firm 
  my 
  own 
  opinion 
  about 
  this 
  matter, 
  by 
  that 
  already 
  expressed 
  by 
  my 
  friend, 
  Dr. 
  

   Schaum, 
  in 
  his 
  report 
  on 
  the 
  progress 
  of 
  Entomology 
  during 
  1851, 
  in 
  Troschel's 
  Archiv. 
  

   From 
  the 
  impossibility 
  of 
  identifying 
  any 
  of 
  Mr. 
  Solier's 
  genera, 
  I 
  have 
  avoided 
  express- 
  

   ing 
  any 
  opinion 
  of 
  them 
  in 
  the 
  following 
  pages. 
  

  

  Such 
  being 
  a 
  brief 
  sketch 
  of 
  the 
  previous 
  investigations 
  made 
  in 
  this 
  family, 
  I 
  have 
  next 
  

   to 
  return 
  my 
  grateful 
  acknowledgments 
  to 
  Dr. 
  Melsheimer 
  for 
  the 
  kind 
  assistance 
  ren- 
  

   dered 
  me 
  by 
  the 
  loan 
  of 
  the 
  typical 
  specimens 
  of 
  all 
  the 
  species 
  described 
  by 
  him: 
  and 
  to 
  

   Dr. 
  T. 
  W. 
  Harris 
  for 
  the 
  loan 
  of 
  several 
  types 
  of 
  species 
  described 
  by 
  Say, 
  and, 
  also, 
  

   for 
  several 
  very 
  interesting 
  nondescript 
  species 
  from 
  his 
  collection. 
  

  

  The 
  descriptions 
  in 
  the 
  following 
  pages 
  are 
  usually 
  diagnoses 
  of 
  the 
  species, 
  as 
  the 
  spe- 
  

   cific 
  characters 
  in 
  most 
  of 
  the 
  genera 
  are 
  very 
  clear 
  and 
  well-defined. 
  In 
  the 
  genera 
  Pe- 
  

   detes, 
  Elater, 
  and 
  Cratonychus, 
  such 
  is 
  not 
  the 
  case, 
  the 
  species 
  being 
  difficult 
  of 
  recogni- 
  

   tion, 
  even 
  when 
  typical 
  specimens 
  are 
  before 
  the 
  student. 
  Long 
  and 
  laboured 
  descrip- 
  

   tions 
  in 
  such 
  cases 
  arc 
  of 
  no 
  avail, 
  and 
  only 
  tend 
  to 
  confuse; 
  in 
  those 
  genera, 
  I 
  have 
  

   thought 
  it 
  better 
  to 
  make 
  the 
  diagnosis 
  include 
  a 
  description 
  of 
  all 
  those 
  parts 
  of 
  the 
  body, 
  

   which, 
  after 
  close 
  comparison 
  of 
  all 
  the 
  species, 
  I 
  have 
  found 
  subject 
  to 
  change 
  of 
  form 
  

  

  * 
  In 
  the 
  first 
  volume 
  of 
  the 
  Zoological 
  Journal, 
  there 
  is 
  a 
  Monograph 
  of 
  Cebrionidrc, 
  by 
  Mr. 
  W. 
  E. 
  Leach, 
  in 
  which 
  

   several 
  species 
  are 
  noted 
  as 
  occurring 
  in 
  North 
  America. 
  As 
  it 
  is 
  unfortunately 
  not 
  possible 
  to 
  recognise 
  any 
  of 
  them, 
  

   the 
  essay 
  will 
  not 
  be 
  referred 
  to 
  in 
  the 
  following 
  pages. 
  

  

  