﻿372 
  A. 
  M. 
  Edwards 
  — 
  Infusorial 
  Earths 
  of 
  Pacific 
  Coast. 
  

  

  ination, 
  to 
  be 
  distinct. 
  So 
  markedly 
  is 
  this 
  the 
  case 
  that 
  we 
  

   not 
  unfrequently 
  find 
  that 
  hasty 
  observers 
  have 
  so 
  classed 
  

   them 
  and 
  even 
  made 
  use 
  of 
  locality 
  for 
  the 
  determination 
  of 
  

   specific 
  distinctions. 
  That 
  the 
  Diatomacese, 
  which 
  are 
  the 
  

   organisms 
  with 
  which 
  I 
  shall 
  most 
  particularly 
  treat 
  in 
  this 
  

   paper, 
  are 
  extremely 
  cosmopolitan 
  in 
  their 
  habits 
  ; 
  in 
  fact, 
  

   perhaps 
  more 
  so 
  than 
  any 
  other 
  group, 
  would 
  seem 
  to 
  be 
  

   already 
  established, 
  but 
  the 
  imperfect 
  state 
  of 
  our 
  knowledge 
  

   of 
  them 
  and 
  their 
  life-history 
  at 
  present, 
  leaves 
  us 
  a 
  great 
  deal 
  

   in 
  the 
  dark 
  as 
  to 
  the 
  full 
  extent 
  of 
  their 
  variation 
  during 
  the 
  

   lapse 
  of 
  time 
  or 
  through 
  local 
  distribution. 
  Much 
  has 
  yet 
  to 
  

   be 
  done 
  in 
  this 
  field 
  of 
  investigation 
  and 
  large 
  and 
  widely 
  

   extended 
  collections 
  made 
  of 
  both 
  the 
  recent 
  and 
  extinct 
  

   forms, 
  before 
  we 
  can 
  assert 
  that 
  we 
  know 
  anything 
  very 
  certain 
  

   with 
  regard 
  to 
  their 
  position 
  in 
  the 
  chain 
  of 
  being, 
  their 
  habits, 
  

   history, 
  or 
  range 
  of 
  variations 
  in 
  time 
  or 
  space. 
  I 
  do 
  not, 
  at 
  

   the 
  present 
  time, 
  desire 
  to 
  go 
  more 
  fully 
  into 
  this 
  branch 
  of 
  

   the 
  subject, 
  merely 
  confining 
  myself 
  to 
  a 
  thorough 
  report 
  

   upon 
  the 
  specimens 
  submitted 
  to 
  me 
  by 
  Mr. 
  Gibbs. 
  The 
  

   student 
  who 
  desires 
  to 
  follow 
  researches 
  in 
  a 
  field 
  which 
  will 
  

   yield 
  profitable 
  returns 
  cannot 
  choose 
  for 
  himself 
  one 
  in 
  which 
  

   less 
  is 
  known, 
  perhaps, 
  than 
  this, 
  and 
  when 
  its 
  applications 
  to 
  

   geology 
  are 
  considered, 
  for 
  my 
  part, 
  I 
  can 
  hardly 
  imagine 
  one 
  

   more 
  enticing. 
  

  

  Below 
  I 
  give 
  a 
  list 
  of 
  the 
  specimens 
  sent 
  to 
  me 
  for 
  examina- 
  

   tion 
  by 
  Mr. 
  Gibbs 
  and 
  which 
  were 
  collected 
  by 
  him 
  during 
  

   the 
  prosecution 
  of 
  the 
  Northwest 
  Boundary 
  Survey. 
  

  

  * 
  Hot 
  spring, 
  Harrison's 
  lake, 
  British 
  Columbia. 
  

  

  Nab 
  chess 
  river, 
  Washington. 
  

  

  Alkaline 
  deposit, 
  Similkamen 
  river, 
  Washington. 
  

  

  * 
  Steilacoom 
  creek, 
  No. 
  1, 
  Washington. 
  

  

  * 
  " 
  " 
  No. 
  2, 
  " 
  

  

  * 
  Point 
  Roberts, 
  " 
  

  

  * 
  Bluff 
  west 
  of 
  Camp 
  Simiahmoo, 
  Washington. 
  

  

  * 
  Camp 
  Simiahmoo, 
  No. 
  1, 
  Washington. 
  

  

  * 
  " 
  « 
  No. 
  2, 
  

  

  Winass 
  river, 
  " 
  

  

  * 
  Point 
  Ludlow, 
  " 
  

  

  Those 
  localities 
  marked 
  with 
  asterisk 
  (*), 
  are 
  from 
  the 
  west 
  

   or 
  coast 
  side 
  of 
  the 
  mountain 
  range, 
  while 
  the 
  others 
  are 
  from 
  

   the 
  eastern 
  slope. 
  This 
  is 
  a 
  point 
  of 
  importance 
  and 
  to 
  be 
  

   borne 
  in 
  mind 
  as 
  will 
  be 
  shown 
  farther 
  on. 
  The 
  principal 
  

   point 
  to 
  be 
  decided 
  in 
  examining 
  these 
  specimens 
  was 
  whether 
  

   they 
  contained 
  any 
  traces 
  of 
  organic 
  remains 
  by 
  means 
  of 
  

   which 
  their 
  marine 
  or 
  fresh 
  water 
  could 
  be 
  determined. 
  There- 
  

   fore 
  they 
  were 
  first 
  superficially 
  examined 
  so 
  as 
  to 
  note 
  if 
  any 
  

  

  