﻿APR 
  S 
  3 
  1904 
  

  

  THE 
  ZOOLOGIST 
  

  

  No. 
  754.— 
  April, 
  1904. 
  

  

  BIOLOGICAL 
  SUGGESTIONS. 
  

  

  RIVEES 
  AS 
  FACTORS 
  IN 
  ANIMAL 
  DISTRIBUTION. 
  

   Part 
  I. 
  — 
  Restrictive 
  Action. 
  

  

  By 
  W. 
  L. 
  Distant. 
  

  

  I 
  believe 
  laws 
  discover 
  themselves 
  to 
  individuals, 
  and 
  not 
  that 
  in- 
  

   dividuals 
  discover 
  laws. 
  — 
  Edw. 
  Forbes. 
  

  

  I 
  think 
  it 
  undesirable 
  to 
  give 
  expression 
  to 
  tbeories 
  which 
  one 
  may 
  

   afterwards 
  feel 
  oneself 
  committed 
  to, 
  as 
  the 
  investigation 
  goes 
  on. 
  ... 
  I 
  

   bave 
  often 
  noticed 
  in 
  my 
  younger 
  sporting 
  days 
  — 
  and 
  it 
  is 
  a 
  fact 
  well 
  known 
  

   to 
  sportsmen 
  — 
  tbat 
  some 
  hounds 
  are 
  apt 
  to 
  give 
  tongue 
  before 
  they 
  have 
  got 
  

   a 
  true 
  scent, 
  whilst 
  there 
  are 
  otbers 
  whose 
  voice 
  can 
  be 
  relied 
  upon. 
  I 
  am 
  

   an 
  old 
  dog, 
  and 
  have 
  always 
  had 
  a 
  disposition 
  to 
  run 
  mute. 
  — 
  Gen. 
  Pitt- 
  

   Rivers. 
  

  

  Some 
  years 
  ago 
  I 
  beguiled 
  many 
  very 
  quiet 
  hours 
  on 
  the 
  

   Transvaal 
  veld 
  by 
  taking 
  stock 
  of 
  my 
  zoological 
  note-books, 
  and 
  

   seeing 
  how 
  far 
  the 
  facts 
  and 
  observations 
  I 
  had 
  accumulated 
  

   could 
  aid 
  me 
  in 
  a 
  solution 
  of 
  some 
  biological 
  questions 
  which 
  I 
  

   had 
  often 
  pondered, 
  but 
  never 
  answered. 
  Among 
  these 
  was 
  the 
  

   part 
  that 
  the 
  principal 
  rivers 
  of 
  the 
  earth 
  had 
  played 
  in 
  the 
  

   cleavage 
  lines 
  of 
  animal 
  distribution. 
  I 
  had 
  no 
  theory, 
  nor 
  did 
  

   I 
  find 
  one 
  ; 
  for, 
  though 
  it 
  seemed 
  clear 
  that 
  rivers 
  undeniably 
  

   were, 
  and 
  had 
  been, 
  barriers 
  to 
  the 
  migration 
  of 
  plants 
  and 
  

   animals, 
  yet, 
  on 
  the 
  other 
  hand, 
  it 
  was 
  equally 
  apparent 
  that 
  

  

  Zool. 
  4th 
  ser. 
  vol. 
  VIII., 
  April, 
  1904. 
  l 
  

  

  