﻿ANATOMY 
  OF 
  THE 
  WESTERN 
  CRICKET. 
  173 
  

  

  than 
  those 
  of 
  the 
  metathorax, 
  or 
  third 
  thoracic 
  segment. 
  The 
  ventral 
  

   piece 
  (sternum) 
  is 
  crescent-shaped, 
  while 
  that 
  of 
  the 
  metathorax 
  is 
  twice 
  

   as 
  large 
  and 
  transversely 
  ovate. 
  

  

  The 
  third 
  segment 
  (meta-thorax) 
  is 
  of 
  the 
  same 
  size 
  as 
  the 
  middle 
  ring, 
  

   but 
  is 
  slightly 
  swollen 
  on 
  the 
  sides, 
  and 
  a 
  slightly 
  marked, 
  indefinite 
  

   swelling 
  above 
  represents 
  the 
  scutellum. 
  The 
  flanks 
  are 
  larger, 
  as 
  they 
  

   afford 
  insertions 
  for 
  the 
  muscles 
  of 
  the 
  much 
  larger 
  hind 
  legs. 
  Both 
  of 
  

   the 
  hinder 
  thoracic 
  segments 
  have 
  broad, 
  flattened, 
  spine-like 
  expansions 
  

   of 
  the 
  sternum 
  ; 
  and 
  on 
  each 
  side 
  of 
  the 
  prothorax 
  is 
  a 
  sharp 
  slender 
  

   spine. 
  The 
  third 
  pair 
  of 
  legs 
  are 
  twice 
  as 
  large 
  as 
  the 
  second. 
  

  

  The 
  breathing 
  holes 
  or 
  spiracles 
  by 
  which 
  the 
  air 
  enters 
  the 
  air-tubes 
  

   within 
  the 
  body, 
  for 
  no 
  insects 
  breathe 
  through 
  their 
  mouths 
  as 
  in 
  the 
  

   higher 
  (vertebrate) 
  animals, 
  are 
  eighteen 
  in 
  number, 
  there 
  being 
  nine 
  

   pairs. 
  The 
  first 
  pair 
  forms 
  a 
  large 
  slit-like 
  opening 
  situated 
  on 
  each 
  

   side 
  of 
  the 
  prothorax, 
  and 
  concealed 
  by 
  the 
  tergum 
  or 
  dorsal 
  piece. 
  The 
  

   second 
  pair 
  are 
  on 
  the 
  sides 
  of 
  the 
  meso-thorax, 
  and 
  are 
  of 
  the 
  same 
  

   size 
  as 
  the 
  eight 
  abdominal 
  pairs 
  which 
  are 
  situated 
  on 
  the 
  eight 
  basal 
  

   abdominal 
  segment. 
  

  

  The 
  wings 
  are 
  concealed 
  by 
  the 
  prothorax 
  ; 
  the 
  fore 
  pair 
  are 
  small 
  and 
  

   rounded, 
  as 
  broad 
  as 
  long 
  ; 
  they 
  are 
  considerably 
  larger 
  in 
  the 
  male 
  

   than 
  in 
  the 
  other 
  sex. 
  The 
  hinder 
  pair 
  are 
  minute, 
  rudimentary, 
  rolled 
  

   up, 
  and 
  flattened 
  down 
  upon 
  the 
  body, 
  but 
  when 
  opened 
  are 
  seen 
  to 
  be 
  

   oval 
  in 
  form. 
  The 
  wings 
  of 
  the 
  female 
  are 
  smaller 
  than 
  those 
  of 
  the 
  

   male; 
  they 
  are 
  flattened, 
  with 
  the 
  veins 
  not 
  strongly 
  marked, 
  and 
  with 
  

   no 
  means 
  for 
  producing 
  sounds. 
  On 
  the 
  contrary, 
  those 
  of 
  the 
  male 
  are 
  

   much 
  larger 
  ; 
  the 
  veins 
  are 
  raised 
  and 
  strongly 
  marked, 
  with 
  the 
  costal 
  

   region, 
  which 
  is 
  full 
  and 
  large, 
  bent 
  down 
  ; 
  the 
  subcostal 
  and 
  median 
  

   veins 
  are 
  large 
  and 
  distinct, 
  while 
  there 
  is 
  a 
  clear 
  oval 
  space 
  between 
  

   the 
  median 
  and 
  outer 
  branch 
  of 
  the 
  submedian. 
  Below 
  and 
  nearer 
  the 
  

   outer 
  edge 
  of 
  the 
  wing 
  is 
  a 
  second 
  large 
  sub 
  triangular, 
  clear, 
  resonant 
  

   space. 
  The 
  main 
  submedian 
  vein 
  is 
  large 
  and 
  much 
  thickened, 
  with 
  a 
  

   row 
  of 
  dense, 
  fine 
  teeth 
  along 
  the 
  middle. 
  This 
  forms 
  the 
  " 
  file" 
  which 
  

   rubs 
  against 
  the 
  other 
  wing. 
  The 
  sound 
  may 
  be 
  produced 
  in 
  an 
  alco- 
  

   holic 
  specimen 
  by 
  rubbing 
  one 
  wing 
  upon 
  the 
  other. 
  The 
  " 
  file" 
  pro- 
  

   duces 
  the 
  sound, 
  the 
  vibrations 
  being 
  rendered 
  audible 
  by 
  the 
  resonant, 
  

   tense, 
  elastic, 
  clear 
  spaces 
  in 
  the 
  other 
  wing, 
  which 
  throw 
  a 
  mass 
  of 
  

   air 
  into 
  pulsations. 
  Thus 
  the 
  file 
  may 
  be 
  compared 
  to 
  a 
  violin 
  bow, 
  the 
  

   veins 
  of 
  the 
  wing 
  to 
  the 
  strings 
  of 
  the 
  violin, 
  and 
  the 
  resonant 
  surfaces 
  

   to 
  the 
  box 
  of 
  the 
  violin, 
  or 
  the 
  elastic 
  wing 
  may 
  be 
  compared 
  to 
  the 
  

   sounding-board 
  of 
  a 
  piano. 
  Not 
  only 
  does 
  one 
  fore 
  wing 
  rub 
  upon 
  the 
  

   other, 
  the 
  rasping 
  noise 
  being 
  produced 
  by 
  partially 
  opening 
  and 
  clos- 
  

   ing 
  the 
  wing, 
  but 
  it 
  seems 
  probable 
  that 
  the 
  file 
  rubs 
  over 
  the 
  stiff? 
  

   horny, 
  upcurved 
  hinder 
  edge 
  of 
  the 
  meso-thoracic 
  segment. 
  At 
  any 
  

   rate 
  the 
  mechanism 
  in 
  the 
  fore 
  wings 
  is 
  amply 
  sufficient 
  to 
  produce 
  the 
  

   sounds 
  referred 
  to 
  by 
  Mr. 
  Thomas 
  rn 
  his 
  notes, 
  wherein 
  he 
  states 
  that 
  

   u 
  the 
  males 
  utter 
  a 
  sharp 
  sound, 
  not 
  much 
  like 
  that 
  of 
  the 
  katydid-like 
  

  

  