﻿158 
  Mr. 
  A. 
  Sanders 
  on 
  the 
  

  

  There 
  are 
  a 
  few 
  memoirs 
  which 
  treat 
  of 
  the 
  brain 
  of 
  Proto- 
  

   pterns 
  or 
  Lqridostre?i 
  which 
  will 
  be 
  referred 
  to 
  in 
  the 
  course 
  

   of 
  this 
  paper. 
  

  

  The 
  specimens 
  on 
  which 
  the 
  present 
  paper 
  is 
  founded 
  were 
  

   caught 
  under 
  my 
  immediate 
  supervision 
  in 
  the 
  River 
  Burnett 
  

   at 
  Gayndah, 
  in 
  Queensland, 
  Australia. 
  

  

  The 
  treatment 
  to 
  which 
  the 
  nervous 
  system 
  was 
  subjected 
  

   was 
  applied 
  before 
  molecular 
  death 
  could 
  take 
  place. 
  

  

  This 
  treatment 
  consists 
  in 
  placing 
  the 
  head 
  immediately 
  

   after 
  it 
  has 
  been 
  cut 
  off 
  into 
  Miiller's 
  solution 
  to 
  which 
  spirits 
  

   of 
  wine 
  has 
  been 
  added 
  in 
  the 
  proportion 
  of 
  one 
  third 
  ; 
  the 
  

   solution 
  is 
  changed 
  next 
  day 
  and 
  again 
  two 
  or 
  three 
  times 
  in 
  

   the 
  course 
  of 
  three 
  weeks 
  : 
  the 
  skull 
  containing 
  the 
  brain 
  is 
  

   then 
  placed 
  in 
  a 
  2-per-cent. 
  solution 
  of 
  potassium 
  bichromate, 
  

   which 
  is 
  changed 
  about 
  once 
  a 
  fortnight, 
  until 
  the 
  brain 
  be- 
  

   comes 
  sufficiently 
  hard 
  to 
  be 
  sectioned 
  ; 
  this 
  occurs 
  at 
  various 
  

   periods, 
  taking 
  a 
  shorter 
  time 
  in 
  the 
  higher 
  Vertebrates 
  than 
  

   in 
  the 
  lower 
  ; 
  in 
  the 
  present 
  case 
  the 
  period 
  extended 
  to 
  more 
  

   than 
  twelve 
  months. 
  

  

  The 
  best 
  staining-fluid, 
  I 
  find, 
  is 
  an 
  aqueous 
  solution 
  of 
  the 
  

   aniline 
  dye 
  known 
  commercially 
  as 
  soluble 
  blue. 
  

  

  This 
  method 
  may 
  seem 
  antiquated 
  to 
  some 
  people, 
  who 
  

   think 
  everything 
  new 
  must 
  be 
  best 
  ; 
  but 
  I 
  have 
  always 
  found 
  

   il 
  to 
  succeed 
  well, 
  and 
  it 
  is 
  of 
  great 
  advantage 
  to 
  persons 
  

   situated 
  as 
  1 
  was, 
  who 
  are 
  not 
  in 
  a 
  position 
  to 
  attend 
  to 
  cutting 
  

   sections 
  for 
  some 
  time 
  after 
  the 
  capture 
  of 
  the 
  animals 
  ; 
  in 
  

   fact 
  I 
  can 
  recommend 
  it 
  as 
  an 
  all-round 
  method 
  for 
  travellers, 
  

   and 
  in 
  cases 
  where 
  the 
  material 
  is 
  too 
  precious 
  to 
  be 
  wasted 
  

   on 
  experiments 
  it 
  is 
  better 
  than 
  most 
  of 
  the 
  new 
  ones, 
  which 
  

   although 
  perhaps 
  for 
  minute 
  points 
  they 
  may 
  be 
  good, 
  yet 
  are 
  

   more 
  or 
  less 
  uncertain, 
  and 
  are 
  therefore 
  not 
  suited 
  for 
  use 
  in 
  

   the 
  bush. 
  

  

  The 
  chromo-silver 
  method 
  of 
  Golgi, 
  for 
  instance, 
  as 
  given 
  

   in 
  Fridtjof 
  Nansen's 
  memoir 
  *, 
  is 
  excellent 
  for 
  showing 
  cell- 
  

   processes 
  of 
  the 
  brain 
  in 
  the 
  higher 
  Vertebrates, 
  but 
  requires 
  

   more 
  civilized 
  surroundings 
  than 
  are 
  to 
  be 
  found 
  in 
  that 
  sort 
  

   of 
  place 
  for 
  its 
  proper 
  carrying 
  out. 
  

  

  Macroscopic 
  Anatomy. 
  

  

  General 
  Description. 
  

  

  The 
  brain 
  (PI. 
  VIII. 
  fig. 
  2) 
  on 
  its 
  ventral 
  side 
  accurately 
  

   fits 
  into 
  a 
  depression 
  in 
  the 
  base 
  of 
  the 
  skull 
  ; 
  but 
  on 
  the 
  

  

  * 
  ' 
  The 
  Structure 
  and 
  Combination 
  of 
  the 
  Histological 
  Elements 
  of 
  

   the 
  Central 
  Nervous 
  System 
  : 
  ' 
  Bergens 
  Museum, 
  1886. 
  

  

  