﻿6 
  JUHLIN-DANNFELT, 
  ON 
  THE 
  DIATOMS 
  OF 
  THE 
  BALTIC 
  SEA. 
  

  

  water, 
  might 
  harbour 
  a 
  much 
  greater 
  number 
  of 
  species, 
  — 
  

   partly 
  marine, 
  partly 
  freshwater- 
  and 
  brackish 
  forms. 
  More- 
  

   over 
  from 
  the 
  Baltic 
  once 
  having 
  been 
  in 
  open 
  counection 
  

   witli 
  the 
  Arctic 
  Ocean, 
  one 
  miglit 
  expect 
  to 
  find 
  some 
  arctic 
  

   forms 
  still 
  existiug 
  tbere. 
  

  

  This 
  supposition, 
  — 
  perhaps 
  save 
  the 
  suspicion 
  of 
  still 
  

   remaining 
  arctic 
  forms, 
  — 
  proved 
  to 
  be 
  correct, 
  when 
  

   ScHUMANN, 
  in 
  his 
  last 
  paper 
  ■^) 
  gave 
  a 
  list 
  of 
  not 
  less 
  than 
  149 
  

   species 
  and 
  9 
  varieties 
  living 
  in 
  the 
  Baltic. 
  This 
  niimber 
  

   ought 
  to 
  be 
  reduced 
  a 
  good 
  deal, 
  for 
  he 
  has 
  readopted 
  a 
  

   great 
  many 
  of 
  Kiitzingian 
  species, 
  which 
  have 
  proved 
  to 
  be 
  

   very 
  little 
  distinct 
  forms, 
  and 
  considering 
  also 
  that 
  Schumann, 
  

   in 
  his 
  last 
  mentioned 
  paper, 
  has 
  a 
  considerable 
  number 
  of 
  

   new 
  species, 
  known 
  to 
  no 
  other 
  author, 
  the 
  diatomaceous 
  

   flora 
  of 
  the 
  Baltic 
  seeraed 
  still 
  well 
  worth 
  of 
  a 
  new 
  exami- 
  

   nation. 
  

  

  In 
  order 
  to 
  contribute 
  in 
  some 
  degree 
  to 
  fill 
  up 
  this 
  

   gap 
  in 
  our 
  knowledge 
  of 
  the 
  lower 
  algae 
  of 
  the 
  Scandinavian 
  

   waters, 
  I 
  have 
  made 
  a 
  number 
  of 
  collections 
  of 
  diatoms 
  along 
  

   the 
  coast 
  of 
  the 
  Baltic 
  from 
  Gefle 
  to 
  Malmö, 
  from 
  Hangö 
  

   to 
  Helsingfors 
  and 
  on 
  the 
  coasts 
  of 
  Gotland 
  and 
  Oland 
  during 
  

   the 
  years 
  1879 
  — 
  1881, 
  — 
  in 
  1880 
  with 
  a 
  subvention 
  from 
  

   the 
  Royal 
  Academy 
  of 
  Science 
  in 
  Stockholm. 
  

  

  Besidcs 
  my 
  own 
  gatherings 
  from 
  these 
  travels, 
  I 
  have 
  

   examined 
  some 
  collections 
  that 
  Prof. 
  P. 
  T. 
  Cleve 
  of 
  Upsala 
  

   has 
  had 
  the 
  kindness 
  to 
  place 
  at 
  my 
  disposal, 
  viz: 
  some 
  

   slides 
  from 
  the 
  Baltic 
  coast 
  of 
  Germany, 
  a 
  little 
  collection 
  

   from 
  the 
  south 
  coast 
  of 
  Finland 
  made 
  by 
  D:r 
  Elfting 
  of 
  

   Helsingfors, 
  and 
  some 
  samples 
  from 
  the 
  Gulf 
  of 
  Bothnia 
  

   and 
  from 
  the 
  coast 
  of 
  Gotland, 
  taken 
  by 
  Prof. 
  Cleve 
  himself. 
  

   Through 
  the 
  kindness 
  of 
  Prof. 
  S. 
  LovÉN 
  of 
  Stockholm 
  I 
  have 
  

   also 
  had 
  the 
  opportunity 
  of 
  examining 
  some 
  bottomsoil 
  speci- 
  

   mens 
  from 
  the 
  south 
  part 
  of 
  the 
  Baltic. 
  

  

  In 
  order 
  to 
  get 
  the 
  following 
  list 
  of 
  Baltic 
  species 
  as 
  

   complete 
  as 
  possible, 
  I 
  have 
  added 
  siich 
  species 
  which 
  are 
  

   indicated 
  by 
  other 
  authors 
  as 
  occurring 
  in 
  the 
  sea 
  here 
  in 
  

   question. 
  Finally, 
  I 
  have 
  also 
  thought 
  proper 
  to 
  add 
  even 
  

   such 
  forms 
  as 
  I 
  have 
  found 
  imbedded 
  in 
  bottomclay 
  from 
  

   the 
  Baltic 
  or 
  in 
  younger 
  earths, 
  evidently 
  formed 
  in 
  the 
  

   brackish 
  water 
  of 
  that 
  sea, 
  though 
  I 
  might 
  neither 
  have 
  

  

  ') 
  SCHUM. 
  1868, 
  

  

  4 
  

  

  