﻿BIVEBS 
  AS 
  FACTORS 
  IN 
  ANIMAL 
  DISTRIBUTION. 
  125 
  

  

  that 
  many 
  other 
  facts 
  and 
  observations 
  bearing 
  on 
  the 
  question 
  

   require 
  collation. 
  As 
  far 
  as 
  his 
  knowledge 
  extends, 
  in 
  a 
  general 
  

   way 
  rivers 
  do 
  not 
  qualify 
  the 
  distribution 
  of 
  genera 
  and 
  species, 
  

   but 
  in 
  a 
  much 
  more 
  limited 
  sense 
  they 
  do, 
  and 
  such 
  facts 
  demand 
  

   consideration. 
  Though 
  Nature 
  works 
  on 
  the 
  same 
  plan, 
  she 
  

   does 
  not 
  always 
  use 
  the 
  same 
  means, 
  and 
  the 
  danger 
  of 
  ad- 
  

   vancing 
  all-sufficing 
  theories, 
  or 
  promoting 
  frequent 
  causation 
  

   to 
  a 
  universal 
  position, 
  is 
  that 
  the 
  equally 
  true 
  though 
  in- 
  

   frequent 
  factors 
  are 
  too 
  often 
  ignored 
  or 
  put 
  out 
  of 
  court 
  

   altogether. 
  Again, 
  great 
  care 
  is 
  necessary 
  in 
  dealing 
  with 
  

   reports 
  made 
  by 
  travellers 
  on 
  these 
  fluviatile 
  divisions, 
  especially 
  

   in 
  areas 
  which 
  have 
  been 
  little 
  zoologically 
  investigated, 
  as 
  sub- 
  

   sequent 
  discovery 
  often 
  proves 
  genera 
  and 
  species 
  to 
  exist 
  where 
  

   their 
  non-extension 
  was 
  regarded 
  as 
  an 
  almost 
  axiom. 
  

  

  Reports 
  on 
  the 
  distributional 
  action 
  of 
  the 
  River 
  Congo 
  will 
  

   illustrate 
  the 
  last 
  remarks. 
  Mr. 
  Monteiro, 
  with 
  reference 
  to 
  the 
  

   southern 
  banks 
  of 
  the 
  river, 
  states 
  : 
  — 
  " 
  The 
  difference 
  in 
  the 
  

   scenery 
  and 
  vegetation 
  from 
  those 
  of 
  the 
  north 
  is 
  very 
  great 
  

   indeed, 
  and 
  not 
  less 
  so 
  is 
  that 
  of 
  the 
  birds 
  and 
  animals 
  (sic). 
  I 
  

   have 
  noticed 
  enough 
  to 
  convince 
  me 
  that 
  it 
  would 
  well 
  repay 
  a 
  

   naturalist 
  to 
  investigate 
  the 
  number 
  of 
  species 
  this 
  river 
  cuts 
  off, 
  

   as 
  it 
  were, 
  from 
  Angola."* 
  " 
  Sharks, 
  so 
  frightfully 
  dangerous 
  

   in 
  the 
  surf 
  of 
  the 
  West 
  Coast, 
  are 
  unknown 
  south 
  of 
  the 
  River 
  

   Congo. 
  I 
  have 
  never 
  heard 
  of 
  a 
  person 
  being 
  attacked 
  by 
  one, 
  

   although 
  at 
  Loanda 
  the 
  white 
  population 
  bathe 
  off 
  the 
  island 
  in 
  

   front 
  of 
  the 
  town, 
  and 
  blacks 
  dabble 
  about 
  in 
  the 
  sea 
  everywhere, 
  

   and 
  swim 
  to 
  and 
  from 
  the 
  boats 
  and 
  barges. 
  "+ 
  The 
  author 
  then 
  

   proceeds 
  with 
  other 
  statements 
  which 
  have 
  been 
  subsequently 
  

   controverted. 
  " 
  The 
  Gorilla 
  and 
  Chimpanzee, 
  for 
  instance, 
  are 
  

   only 
  known 
  north 
  of 
  the 
  Congo 
  ; 
  they 
  are 
  found 
  at 
  Loango 
  and 
  

   Landana, 
  and, 
  from 
  reports 
  of 
  the 
  natives, 
  even 
  near 
  to 
  the 
  

   river 
  itself 
  ; 
  many 
  species 
  of 
  monkeys, 
  very 
  abundant 
  at 
  Cabinda 
  

  

  "the 
  Oregon 
  or 
  Columbia, 
  as 
  it 
  is 
  sometimes 
  called, 
  forms 
  a 
  remarkable 
  

   botanical 
  line, 
  which 
  is 
  the 
  boundary 
  of 
  the 
  Californian 
  flora." 
  In 
  Cali- 
  

   fornia, 
  Mr. 
  Hincliff 
  travelled 
  along 
  by 
  the 
  side 
  of 
  a 
  small 
  river 
  where 
  the 
  

   countless 
  lupines 
  were 
  all 
  white 
  on 
  one 
  bank, 
  and 
  all 
  blue 
  on 
  the 
  other 
  (' 
  Over 
  

   the 
  Sea 
  and 
  Far 
  Away,' 
  p. 
  247). 
  

  

  ;: 
  ' 
  Angola/ 
  vol. 
  i. 
  p. 
  53. 
  

  

  f 
  Ibid. 
  p. 
  51. 
  

  

  