﻿THE 
  BRAIN 
  OF 
  THE 
  LOCUST. 
  241 
  

  

  that 
  tliere 
  is 
  a 
  partial 
  nervous 
  communication 
  between 
  the 
  trabecule 
  and 
  

   the 
  commissural 
  lobes. 
  The 
  fibers 
  enveloping 
  the 
  trabecula 
  above 
  are 
  

   more 
  numerous, 
  the 
  mass 
  of 
  fibers 
  much 
  thicker 
  than 
  in 
  section 
  10, 
  

   showing 
  that 
  what 
  we 
  supposed 
  to 
  be 
  fibers 
  separating 
  the 
  stalk 
  from 
  

   the 
  trabecula 
  appear 
  to 
  be 
  really 
  such. 
  

  

  A 
  broad 
  bundle 
  of 
  fibers 
  is 
  also 
  seen 
  on 
  the 
  right 
  side, 
  passing 
  down 
  

   from 
  the 
  upper 
  side 
  inside 
  of 
  the 
  upper 
  end 
  of 
  the 
  peduncle, 
  down 
  out- 
  

   side 
  and 
  back 
  of 
  the 
  central 
  body, 
  and 
  to 
  enter 
  the 
  commissural 
  lobe 
  on 
  

   its 
  inner 
  side, 
  terminating 
  at 
  the 
  point 
  where 
  the 
  ascending 
  fibers 
  to 
  the 
  

   upper 
  side 
  of 
  the 
  trabecula 
  originate. 
  There 
  is 
  thus 
  a 
  direct 
  communica- 
  

   tion 
  between 
  the 
  upper 
  part 
  of 
  the 
  brain 
  and 
  the 
  oesophageal 
  commissure 
  

   in 
  the 
  lower 
  part. 
  It 
  appears, 
  also, 
  that 
  three 
  large 
  nerves 
  or 
  bundles 
  

   of 
  fibers 
  enter 
  each 
  commissural 
  lobe 
  from 
  above. 
  

  

  At 
  the 
  under 
  side 
  of 
  the 
  commissural 
  lobes 
  the 
  cortical 
  ganglion 
  cells 
  

   (some 
  of 
  them 
  very 
  large) 
  appear 
  to 
  send 
  their 
  fibers 
  into 
  others 
  to 
  build 
  

   up 
  the 
  mass 
  of 
  fibers 
  enveloping 
  the 
  lobe. 
  Flogel 
  states 
  that 
  the 
  opinion 
  

   that 
  the 
  ganglionic 
  cells 
  in 
  winged 
  insects 
  are 
  in 
  direct 
  relation 
  through 
  

   the 
  fibers 
  with 
  the 
  organs 
  of 
  the 
  body 
  are 
  unfortunately 
  provisionally 
  

   contradicted 
  by 
  his 
  observations. 
  But 
  here 
  (seen 
  in 
  a 
  portion 
  of 
  the 
  

   commissural 
  lobe 
  not 
  represented 
  in 
  Fig. 
  3 
  of 
  PI. 
  XI), 
  as 
  in 
  one 
  or 
  two 
  

   other 
  places, 
  we 
  think 
  we 
  have 
  seen 
  fibers 
  from 
  the 
  cortical 
  ganglion 
  cells 
  

   passing 
  into 
  and 
  aiding 
  in 
  building 
  up 
  the 
  nerves. 
  Such 
  a 
  relation 
  is 
  

   very 
  plain 
  in 
  the 
  brain 
  of 
  the 
  horseshoe-crab, 
  IAmulus 
  polypliemus. 
  

  

  LIST 
  OF 
  WORKS 
  ON 
  THE 
  INTERNAL 
  STRUCTURE 
  OF 
  THE 
  BRAIN 
  OF 
  

   CRUSTACEA 
  AND 
  INSECTS. 
  

  

  Dujaedix. 
  Memoirs 
  sur 
  le 
  Systeine 
  nerveaux 
  des 
  Insectes. 
  Par. 
  F. 
  Dujardin. 
  An- 
  

   nates 
  des 
  Sciences 
  naturelles. 
  Ser. 
  3. 
  1850. 
  Tom. 
  xiv, 
  p. 
  195-206, 
  tab. 
  1, 
  1850. 
  

   Ofsiannikoff. 
  Ueber 
  die 
  feinerer 
  Structur 
  des 
  Kopfganglions 
  bei 
  den 
  Krebsen, 
  be- 
  

  

  sonders 
  beim 
  Palinurus 
  locusta. 
  Von 
  Ph. 
  Ofsiannikof. 
  Me"m. 
  Acad. 
  Imp. 
  Sc. 
  St. 
  

  

  Petersbourg. 
  Tom. 
  vi, 
  No. 
  10, 
  1863. 
  Plate 
  i. 
  

   Leydig. 
  Voin 
  Ban 
  des 
  thieriscben 
  Korpers. 
  Von 
  F. 
  Leydig. 
  Tubingen, 
  1864, 
  p. 
  

  

  214-226. 
  

   Rabl-Ruckhard. 
  Studien 
  uber 
  Insectengehirne. 
  Von 
  Rabl-Ruckhard. 
  Archiv 
  fur 
  

  

  Anatomie, 
  Pbysiologie, 
  etc., 
  berausg. 
  von 
  Reicbert 
  u. 
  R. 
  Du 
  Bois-Raymond, 
  Jan. 
  

  

  1876, 
  p. 
  480. 
  Plate 
  i. 
  

   Dietl. 
  Die 
  Organization 
  des 
  Artbropodengebirns. 
  Von 
  M. 
  J. 
  Dietl. 
  Zeitscbr. 
  wis- 
  

  

  senscb. 
  Zool. 
  Bd. 
  27, 
  1876, 
  p. 
  488. 
  Plates 
  xxxvi-xxxviii. 
  

   Berger. 
  Memoir, 
  by 
  E. 
  Berger, 
  in 
  Arbeiten 
  des 
  zoologiscben 
  Instituts 
  zu 
  Wien. 
  Bd. 
  

  

  i, 
  Heft, 
  ii, 
  p. 
  173, 
  1878. 
  

   Flogel. 
  Ueber 
  den 
  einbeitlicben 
  Bau 
  des 
  Gehirns 
  in 
  den 
  verscbiedenen 
  Insectenord- 
  

  

  nungen. 
  Von 
  J. 
  H. 
  L. 
  Flogel. 
  Zeitscbr. 
  wissenscb. 
  Zoologie. 
  Bd. 
  xxx, 
  suppl. 
  

  

  1878, 
  p. 
  556. 
  Plates 
  xxiii, 
  xxiv. 
  

   Newton. 
  On 
  the 
  Brain 
  of 
  the 
  Cockroach, 
  Blatta 
  orientalis. 
  By 
  E. 
  T. 
  Newton. 
  

  

  Quart. 
  Journ. 
  Microscopical 
  Science, 
  July, 
  1879, 
  p. 
  340. 
  Plates 
  xv, 
  xvi. 
  

   Graber. 
  Ueber 
  das 
  unicorneale 
  Tracheaten, 
  und 
  speciell 
  das 
  Aracbnoidecn- 
  und 
  

  

  Myriopoden-Auge. 
  Von. 
  V. 
  Graber. 
  Archiv 
  fiir 
  mikroskopischo 
  Anatomic. 
  Bd. 
  

  

  xvii, 
  Bonn., 
  1879, 
  p. 
  58-93. 
  (Gives 
  a 
  sketch 
  on 
  pi. 
  vi 
  of 
  the 
  brain 
  of 
  Joins 
  sabu- 
  

  

  losus 
  and 
  Litbobius 
  forficatus.) 
  Taf. 
  v-vii. 
  

   Michels. 
  Beschreibung 
  des 
  nervensystems 
  von 
  Oryctes 
  nasicornis 
  in 
  Larven, 
  Pup- 
  

   16 
  L 
  

  

  