﻿,i 
  SENSE 
  ORGANS 
  OF 
  THE 
  LOCUST. 
  189 
  

  

  much 
  as 
  this 
  layer 
  is 
  homologous 
  with 
  the 
  epidermis 
  of 
  other 
  animals, 
  

   it 
  seems 
  desirable 
  to 
  secure 
  uniformity 
  of 
  nomenclature 
  by 
  adopting 
  this 
  

   name 
  for 
  the 
  subcuticular 
  layer 
  of 
  cells. 
  I 
  have 
  not 
  devoted 
  much 
  at- 
  

   tention 
  to 
  this 
  tissue. 
  Its 
  relations 
  and 
  proportionate 
  size 
  in 
  locusts 
  to 
  

   the 
  cuticula, 
  Gu., 
  can 
  be 
  seen 
  at 
  Up., 
  in 
  Fig. 
  7. 
  The 
  cells 
  composing 
  it 
  

   are 
  cylindrical 
  and 
  form 
  but 
  a 
  single 
  layer, 
  interspersed 
  through 
  which 
  

   are 
  numerous 
  hair 
  cells, 
  as 
  above 
  described. 
  

  

  In 
  An 
  ah 
  nix, 
  the 
  epidermis 
  is 
  composed 
  of 
  high 
  cylinder- 
  cells, 
  which 
  

   contain 
  a 
  great 
  deal 
  of 
  granular 
  pigment, 
  often 
  sufficient 
  to 
  completely 
  

   hide 
  the 
  nucleus. 
  Seen 
  from 
  the 
  surface 
  these 
  cells 
  present 
  polygonal 
  

   outlines 
  (Fig. 
  5G). 
  When 
  in 
  such 
  a 
  view 
  the 
  nucleus 
  is 
  visible, 
  the 
  

   character 
  of 
  the 
  cuticular 
  matrix 
  is 
  at 
  once 
  evident, 
  and 
  it 
  becomes 
  certain 
  

   that 
  Leydig 
  was 
  entirely 
  wrong 
  in 
  his 
  assertion 
  that 
  the 
  " 
  hypodermis 
  n 
  

   of 
  insects 
  is 
  formed 
  by 
  connective 
  tissue 
  and 
  not 
  by 
  an 
  epithelium. 
  This 
  

   mistake 
  has 
  already 
  been 
  carefully 
  and 
  accurately 
  pointed 
  out 
  by 
  

   Graber. 
  231 
  

  

  The 
  coloration 
  of 
  Anabrus 
  depends 
  principally 
  upon 
  the 
  pigment 
  of 
  

   the 
  epidermis 
  shining 
  through 
  the 
  cuticula. 
  Most 
  of 
  the 
  cells 
  contain 
  

   dull 
  reddish-brown 
  granules, 
  but 
  scattered 
  in 
  among 
  them 
  are 
  patches 
  

   of 
  cells 
  bright 
  green 
  in 
  color. 
  I 
  have 
  observed 
  no 
  cells 
  intermediate 
  

   in 
  color 
  ; 
  on 
  the 
  contrary 
  the 
  passage 
  is 
  abrupt, 
  a 
  brown 
  or 
  red 
  cell 
  lying 
  

   next 
  a 
  green 
  one. 
  Indeed 
  I 
  have 
  never 
  seen 
  any 
  microscopic 
  object 
  

   more 
  bizarre 
  than 
  a 
  piece 
  of 
  the 
  epidermis 
  of 
  Anabrus 
  spread 
  out 
  and 
  

   viewed 
  from 
  the 
  surface. 
  My 
  thought 
  upon 
  first 
  seeing 
  such 
  a 
  prepara- 
  

   tion 
  was 
  that 
  my 
  reagents 
  must 
  have 
  played 
  me 
  some 
  trick, 
  but 
  prepa- 
  

   rations 
  made 
  from 
  alcoholic 
  specimens, 
  and 
  examined 
  in 
  alcohol, 
  without 
  

   having 
  been 
  exposed, 
  to 
  my 
  knowledge, 
  to 
  any 
  other 
  reagent, 
  exhibited 
  

   the 
  same 
  peculiarities. 
  

  

  The 
  student 
  will 
  find 
  observations 
  on 
  the 
  coloration 
  of 
  the 
  epidermis 
  

   and 
  cuticula 
  of 
  insects 
  in 
  an 
  article 
  by 
  Dr. 
  Hagen, 
  232 
  and 
  a 
  memoir 
  by 
  

   Leydig. 
  233 
  

  

  Sense 
  organs. 
  — 
  This 
  would 
  be 
  the 
  proper 
  place 
  to 
  describe 
  the 
  sense 
  

   organs, 
  the 
  eyes, 
  and 
  auditory 
  apparatus, 
  &c, 
  but 
  the 
  extreme 
  difficulty 
  

   of 
  preparing 
  these 
  organs 
  satisfactorily 
  induced 
  me 
  to 
  neglect 
  them 
  

   entirely, 
  in 
  order 
  to 
  devote 
  my 
  whole 
  time 
  to 
  the 
  investigation 
  of 
  other 
  

   points, 
  concerning 
  which 
  results 
  were 
  more 
  readily 
  attainable. 
  For 
  the 
  

   convenience 
  of 
  those 
  who 
  may 
  wish 
  to 
  know 
  the 
  present 
  state 
  of 
  our 
  

   knowledge 
  concerning 
  these 
  obscure 
  structures, 
  I 
  quote 
  below 
  the 
  titles 
  

   v 
  of 
  some 
  of 
  the 
  more 
  important 
  recent 
  papers, 
  234 
  especially 
  those 
  which 
  

   give 
  references 
  to 
  the 
  earlier 
  publications. 
  

  

  ^Graber: 
  Denkscbr. 
  Wien. 
  Akad. 
  wiss. 
  Bel. 
  xxxvi. 
  (1876), 
  p. 
  33. 
  

  

  233 
  Hagen: 
  American 
  Naturalist, 
  vol. 
  vi, 
  p. 
  388. 
  

  

  233 
  Leydig: 
  Bemerkungen 
  iiber 
  die 
  Farben 
  der 
  Hautdecke, 
  etc., 
  bei 
  Insekten. 
  A. 
  f. 
  m. 
  A., 
  Bd. 
  xiii, 
  s. 
  

   536 
  (1876). 
  

  

  234 
  Leydig: 
  Gerucbs-uiid 
  Gehororgan 
  der 
  Krebse 
  and 
  Tn3ekten. 
  Miiller's 
  Archiv., 
  1860, 
  p. 
  292. 
  

  

  Wolf: 
  Das 
  Riechorgan 
  der 
  Biene. 
  Nova. 
  Acta, 
  xxxviii., 
  No. 
  1. 
  

  

  Qrobbeti: 
  TJeber 
  Blascnenfdnnigo 
  Sinnesorgane 
  der 
  Larve 
  von 
  Ptycboptera 
  contaminata. 
  Sitzbor. 
  

   Wien. 
  Akad.. 
  Bd. 
  lxxii. 
  (1876). 
  (List 
  oontinned 
  on 
  next 
  page.) 
  

  

  , 
  

  

  