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  beetle 
  (Epicauta), 
  which 
  passes 
  through 
  three 
  larval 
  stages 
  before 
  

   transforming 
  to 
  a 
  pupa. 
  He 
  divides 
  the 
  life-history 
  of 
  this 
  beetle 
  into 
  

   the 
  following 
  stages: 
  (1) 
  Triungulin; 
  (2) 
  second 
  larva 
  [a, 
  Oarabidoid; 
  

   b, 
  ultimate 
  or 
  Scarabseidoid 
  stage) 
  ; 
  (3) 
  pseudo-pupa, 
  or 
  coarctate 
  larva 
  ; 
  

  

  (4) 
  third 
  larva 
  (closely 
  resembling 
  the 
  Scarabseidoid 
  stage 
  of 
  second) 
  j 
  

  

  (5) 
  true 
  pupa 
  ; 
  (6) 
  beetle. 
  (The 
  reader 
  should 
  examine 
  the 
  figures 
  in 
  PL 
  

   TV 
  of 
  the 
  First 
  Eeport 
  ; 
  otherwise 
  he 
  cannot 
  understand 
  the 
  following 
  

   remarks.) 
  

  

  It 
  appears, 
  then, 
  that 
  the 
  first 
  larva, 
  or 
  triungulin, 
  in 
  form 
  resembles 
  

   the 
  Campodea-like 
  primitive 
  larval 
  form 
  of 
  Ooleoi)tera 
  ; 
  the 
  Epicauta 
  

   triungulin 
  closely 
  resembles 
  a 
  Oarabid 
  larva, 
  the 
  head, 
  antennae, 
  and 
  

   mouth-parts, 
  as 
  well 
  as 
  the 
  legs 
  and 
  form 
  of 
  the 
  body 
  in 
  general, 
  being 
  

   on 
  the 
  primitive, 
  Oarabid 
  type 
  (somewhat 
  like 
  Oasnonia 
  ('^), 
  Galerita 
  

   and 
  Harpalus); 
  the 
  second 
  larva, 
  a, 
  Oarabidoid 
  stage, 
  though 
  quite 
  

   difterent 
  as 
  regards 
  the 
  mouth-parts, 
  and 
  with 
  a 
  smaller 
  head, 
  thicker 
  

   body 
  and 
  much 
  shorter 
  legs, 
  still 
  adheres 
  to 
  the 
  higher 
  Oarabid 
  form 
  

   (Oarabus'and 
  allies). 
  During 
  the 
  Scarabseidoid 
  stage 
  the 
  second 
  larva 
  

   rests 
  nearly 
  motionless 
  in 
  the 
  egg 
  of 
  the 
  locust, 
  and 
  is 
  like 
  the 
  curved,, 
  

   clumsy 
  larvae 
  of 
  the 
  cockchafer 
  or 
  June 
  beetle 
  and 
  other 
  Lamellicorn. 
  

   larvse, 
  which 
  also 
  have 
  the 
  similar 
  habits 
  of 
  lying 
  still 
  in 
  their 
  bur- 
  

   rows 
  and 
  feeding 
  on 
  the 
  roots 
  of 
  grass, 
  or, 
  as 
  in 
  the 
  case 
  of 
  Osmo- 
  

   derma, 
  lying 
  nearly 
  motionless 
  in 
  their 
  cells 
  in 
  rotten 
  wood. 
  This 
  sort 
  

   of 
  life 
  going 
  on, 
  the 
  larval 
  blister 
  beetle 
  after 
  six 
  or 
  seven 
  days 
  assumes 
  

   the 
  ultimate 
  stage 
  of 
  the 
  second 
  larva, 
  and 
  now, 
  from 
  apparent 
  con- 
  

   tinued 
  disuse, 
  the 
  mouth-parts 
  and 
  legs 
  become 
  more 
  aborted 
  than 
  

   before, 
  and 
  the 
  insect 
  in 
  this 
  stage 
  may 
  be 
  compared 
  to 
  some 
  Lon- 
  

   gicorn 
  larvse, 
  with 
  a 
  general 
  resemblance 
  in 
  the 
  curved, 
  cylindrical 
  body 
  

   to 
  the 
  Ptinid 
  and 
  Ohrysomelid, 
  and 
  it 
  even 
  approximates 
  in 
  general 
  shape 
  

   Ourculionid 
  larvse. 
  In 
  the 
  pseudo-pupa 
  or 
  coarctate 
  larva 
  this 
  process 
  of 
  

   disuse 
  and 
  obsolescence 
  of 
  parts 
  culminates 
  in 
  the 
  immobile 
  stage 
  pre- 
  

   ceding 
  (with 
  the 
  intervention 
  of 
  third 
  larva) 
  the 
  pupal 
  condition. 
  We 
  

   thus 
  see 
  that 
  in. 
  the 
  life-history 
  of 
  a 
  single 
  species 
  of 
  beetle, 
  change 
  in 
  

   habits 
  or 
  environment, 
  as 
  well 
  as 
  in 
  the 
  food, 
  induces 
  change 
  in 
  the 
  form 
  

   of 
  the 
  body 
  ; 
  and 
  this 
  series 
  of 
  changes 
  in 
  the 
  Meloidse 
  typifies 
  the 
  suc- 
  

   cessive 
  steps 
  in 
  the 
  degradation 
  of 
  form 
  which 
  characterize 
  the 
  series 
  of 
  

   Ooleopterous 
  larva) 
  from 
  the 
  Oarabidse 
  down 
  to 
  the 
  Ourculionidie 
  and 
  

   Scolytidse. 
  At 
  first 
  all 
  larvse 
  were 
  carnivorous 
  and 
  active 
  in 
  their 
  habits, 
  

   with 
  large 
  mandibles 
  and 
  well 
  developed 
  accessory 
  jaws 
  and 
  legsj 
  cer- 
  

   tain 
  forms 
  then 
  becoming 
  scavengers, 
  their 
  appendages 
  became, 
  from? 
  

   disuse, 
  less 
  developed 
  j 
  then 
  others, 
  becoming 
  phytophagous, 
  became 
  in 
  

   some 
  cases 
  still 
  less 
  developed, 
  the 
  jaws 
  shorter 
  and 
  toothless, 
  with 
  cor- 
  

   resi)onding 
  modifications 
  in 
  the 
  other 
  mouth-parts, 
  the 
  antennse 
  and 
  the 
  

   legs, 
  while 
  the 
  body 
  became 
  thick, 
  fat 
  and 
  cylindrical; 
  until 
  in 
  the 
  wood- 
  

   boring 
  and 
  seed- 
  or 
  nut-inhabiting 
  weevils 
  the 
  antennae 
  and 
  maxillse 
  be- 
  

   came 
  rudimentary, 
  almost 
  disappearing, 
  while 
  the 
  legs 
  utterly 
  vanished. 
  

   Change 
  of 
  habits 
  and 
  surroundings, 
  with 
  corresponding 
  changes 
  in 
  the 
  

  

  