﻿400 
  

  

  AXXUAL 
  EEPORT 
  SMITHSOXL\X 
  IXSTITUTIOX, 
  192 
  9 
  

  

  marks 
  the 
  articulation 
  of 
  the 
  radial 
  vein 
  (fig. 
  12, 
  R) 
  with 
  the 
  second 
  

   axillaiy 
  sclerite 
  {2 
  Ax). 
  The 
  role 
  that 
  the 
  axillary 
  triangle 
  plays 
  in 
  the 
  

   folding 
  of 
  the 
  \\dng 
  will 
  be 
  discussed 
  in 
  Section 
  IV 
  of 
  this 
  paper. 
  

  

  The 
  area 
  of 
  the 
  wing 
  distal 
  to 
  the 
  axillary 
  region 
  comprises 
  the 
  three 
  

   parts 
  of 
  the 
  wing 
  separated 
  by 
  the 
  vannal 
  and 
  jugal 
  folds 
  (fig. 
  10 
  B, 
  

   ij', 
  jf), 
  when 
  these 
  folds 
  are 
  present. 
  The 
  area 
  anterior 
  to 
  the 
  vannal 
  

   fold 
  (fig. 
  14, 
  Rm), 
  containing 
  the 
  costal, 
  subcostal, 
  radial, 
  medial, 
  and 
  

   cubital 
  veins 
  (fig. 
  10 
  B), 
  is 
  the 
  part 
  of 
  the 
  wing 
  chiefly 
  productive 
  of 
  the 
  

   movements 
  of 
  flight, 
  since 
  it 
  is 
  directly 
  afi'ected 
  by 
  the 
  motor-wing 
  

  

  C 
  Sc 
  R 
  M 
  

  

  Rm 
  

  

  2Cu 
  ^V 
  iCu 
  vf 
  A 
  

  

  Sc 
  R+M 
  iCu 
  2Cu 
  M 
  Re 
  C 
  R. 
  

  

  Figure 
  15.— 
  The 
  wings 
  of 
  a 
  grasshopper 
  (Dissosteira 
  Carolina) 
  . 
  A, 
  Left 
  fore- 
  

   wing. 
  B, 
  Left 
  hind 
  wing. 
  Lettering 
  as 
  on 
  Figure 
  10 
  B. 
  The 
  great 
  fan 
  of 
  

   the 
  hind 
  wing 
  posterior 
  to 
  the 
  vannal 
  fold 
  (vf) 
  is 
  possibly 
  the 
  combined 
  

   vannal 
  and 
  jugal 
  regions 
  

  

  muscler,. 
  This 
  part 
  of 
  the 
  wing, 
  therefore, 
  we 
  may 
  term 
  the 
  remigial 
  

   area 
  of 
  the 
  wing 
  (Latin 
  lemigium, 
  an 
  oar)-. 
  The 
  region 
  between 
  the 
  

   vannal 
  and 
  jugal 
  folds 
  is 
  the 
  part 
  of 
  the 
  wing 
  here 
  termed 
  the 
  vannus, 
  

   or 
  vannal 
  region 
  (fig. 
  14, 
  V), 
  though 
  ordinarily 
  called 
  the 
  anal 
  region. 
  

   The 
  vannal 
  veins 
  typically 
  spread 
  out 
  like 
  the 
  ribs 
  of 
  a 
  fan, 
  and, 
  as 
  we 
  

   have 
  seen, 
  their 
  bases 
  are 
  associated 
  with, 
  or 
  supported 
  by, 
  the 
  distal 
  

   end 
  of 
  the 
  third 
  axillary 
  sclerite. 
  (Fig. 
  10 
  B.) 
  In 
  some 
  insects 
  the 
  

   vannus 
  becomes 
  so 
  large, 
  as 
  in 
  the 
  hind 
  wings 
  of 
  grasshoppers 
  and 
  

   katydids 
  (fig. 
  15 
  B), 
  that 
  it 
  forms 
  an 
  efficient 
  gliding 
  surface 
  which 
  

  

  