﻿PLATE 
  XL 
  

  

  FlQ. 
  1. 
  — 
  Section 
  19 
  (X 
  \ 
  A.), 
  passing 
  through 
  the 
  back 
  of 
  the 
  brain, 
  showing 
  the 
  pos- 
  

   terior 
  edge 
  of 
  the 
  calices 
  and 
  antennal 
  lobes 
  and 
  oesophageal 
  commissural 
  

   nerves 
  and 
  optic 
  nerve, 
  tr., 
  small 
  tracheae. 
  

  

  FiG. 
  2. 
  — 
  Section 
  20, 
  passing 
  through 
  the 
  back 
  of 
  the 
  brain, 
  showing 
  the 
  relation 
  of 
  

   the 
  optic 
  nerve 
  to 
  the 
  optic 
  ganglion 
  and 
  eye 
  ; 
  the 
  cornea, 
  cones, 
  rods, 
  and 
  

   retina 
  of 
  the 
  eye 
  are 
  shown; 
  X 
  i 
  A. 
  sup. 
  n., 
  superior, 
  m. 
  n., 
  median, 
  and 
  

   inf. 
  n., 
  inferior 
  commissural 
  nerves 
  connecting 
  the 
  hemispheres. 
  

  

  FiG. 
  3. 
  — 
  Enlarged 
  view 
  of 
  upper 
  part 
  of 
  the 
  stalk 
  and 
  calyx, 
  and 
  the 
  ganglion 
  cells 
  

   surrounding 
  and 
  filling 
  the 
  latter 
  ; 
  X 
  225 
  diameters. 
  3 
  a, 
  &, 
  c, 
  d, 
  different 
  

   ganglion 
  cells 
  seen 
  from 
  different 
  directions, 
  3 
  c 
  showing 
  the 
  large 
  nucleus 
  

   filled 
  with 
  coarse 
  granules, 
  but 
  showing 
  no 
  nucleolus 
  ; 
  one, 
  however, 
  is 
  seen 
  

   in 
  Fig. 
  3 
  &. 
  ncl. 
  ; 
  X 
  725 
  diameters. 
  

  

  FiG. 
  4. 
  — 
  Longitudinal 
  section 
  of 
  the 
  brain 
  and 
  subcesophageal 
  ganglion, 
  magnified 
  

   50 
  diameters, 
  showing 
  the 
  relations 
  between 
  the 
  two, 
  and 
  of 
  the 
  origiu 
  of 
  

   the 
  oesophageal 
  commissure 
  from 
  the 
  upper 
  side 
  of 
  each 
  ganglion, 
  i. 
  e., 
  

   from 
  the 
  back 
  of 
  the 
  brain 
  and 
  the 
  upper 
  side 
  of 
  the 
  subcesophageal 
  gan- 
  

   glion. 
  

  

  FiG. 
  5. 
  — 
  Enlarged 
  view 
  ( 
  X 
  i 
  B) 
  of 
  the 
  subcesophageal 
  ganglion 
  of 
  Fig. 
  6, 
  PL 
  X, 
  show- 
  

   ing 
  the 
  origin 
  of 
  the 
  commissure 
  to 
  the 
  first 
  thoracic 
  ganglion, 
  and 
  on 
  the 
  

   under 
  side 
  the 
  three 
  lobes 
  (mandibular, 
  maxillary, 
  and 
  labial), 
  whence 
  the 
  

   nerves 
  are 
  sent 
  to 
  the 
  mouth-appendages, 
  mand. 
  I., 
  mandibular 
  lobe; 
  

   max. 
  I., 
  maxillary, 
  and 
  max. 
  I'., 
  2d 
  maxillary 
  or 
  labial 
  lobe; 
  com., 
  commis- 
  

   sure 
  to 
  subcesophageal 
  ganglion. 
  

  

  