﻿1 
  890. 
  J 
  BOTANICAL 
  GAZETTE. 
  7 
  

  

  with 
  regard 
  to 
  the 
  origin 
  of 
  the 
  Salviniacea^, 
  which 
  are 
  cer- 
  

   tainly 
  not 
  closely 
  related 
  to 
  the 
  Marsiliacea^.^ 
  

  

  With 
  our 
  very 
  imperfect 
  knowledge 
  of 
  the 
  oophyte 
  of 
  the 
  

   Ophioglosse^e, 
  it 
  would 
  be 
  rash 
  to 
  assume 
  that 
  the 
  group 
  

   originated 
  from 
  the 
  Anthocerotene 
  ; 
  indeed 
  there 
  are 
  very 
  

   strong 
  objections 
  to 
  be 
  brought 
  against 
  such 
  a 
  view. 
  In 
  spite 
  

   of 
  the 
  resemblance 
  of 
  the 
  sexual 
  organs 
  of 
  the 
  Anthoceroteae 
  

   to 
  those 
  of 
  the 
  Marattiacece, 
  they 
  are 
  nevertheless 
  in 
  their 
  

   development 
  much 
  more 
  like 
  those 
  of 
  the 
  other 
  liverworts. 
  

   Again, 
  the 
  Anthocerotea^ 
  are 
  peculiar 
  in 
  the 
  single 
  large 
  

   chloroplast 
  in 
  each 
  cell 
  ; 
  recalling 
  strongly, 
  in 
  this 
  particular, 
  

   such 
  algae 
  as 
  Coleoch^ete, 
  where 
  this 
  is 
  also 
  the 
  case, 
  and 
  

   suggesting 
  a 
  possible 
  derivation 
  from 
  similar 
  forms. 
  

  

  Nevertheless, 
  since 
  in 
  Anthoceros 
  there 
  are 
  such 
  striking 
  

   resemblances 
  to 
  the 
  oophyte 
  of 
  the 
  Marattiaceie, 
  and 
  the 
  

   sporogonium 
  becomes 
  so 
  nearly 
  independent, 
  w^e 
  can 
  readily 
  

   conceive 
  of 
  some 
  allied 
  form 
  with 
  chloroplasts 
  of 
  the 
  ordi- 
  

   nary 
  type, 
  and 
  with 
  sexual 
  organs 
  approximating 
  still 
  more 
  

   closely 
  those 
  of 
  the 
  pteridophytes, 
  in 
  which 
  by 
  the 
  develop- 
  

   ment 
  of 
  a 
  root 
  the 
  sporogonium 
  would 
  become 
  entirely 
  inde- 
  

   pendent. 
  It 
  would 
  be 
  but 
  a 
  step 
  from 
  such 
  a 
  form 
  to 
  the 
  

   simpler 
  Ophioglosse^* 
  

  

  Bower^'^ 
  admits 
  that 
  some 
  such 
  view 
  as 
  the 
  one 
  advanced 
  

   here 
  is 
  capable 
  of 
  defense, 
  but 
  does 
  not 
  believe 
  it 
  to 
  be 
  the 
  

   true 
  one. 
  He 
  does 
  not, 
  however, 
  nor 
  does 
  any 
  other 
  botanist^^ 
  

   so 
  far 
  as 
  I 
  know, 
  give 
  any 
  satisfactory 
  explanation 
  of 
  the 
  ori- 
  

   gin 
  of 
  the 
  sporophyte 
  of 
  Hymenophyllum 
  from 
  any 
  known 
  

   or 
  even 
  h^^pothetical 
  ancestral 
  form. 
  

  

  From 
  the 
  foregoing 
  pages 
  it 
  is 
  evident 
  that 
  there 
  is 
  some- 
  

   thing, 
  at 
  least, 
  to 
  be 
  said 
  in 
  favor 
  of 
  assuming 
  that 
  Ophio- 
  

   glossum 
  and 
  the 
  other 
  eusporangiate 
  ferns 
  are 
  primitive 
  rather 
  

   than 
  derivative 
  forms, 
  but 
  until 
  the 
  life-history 
  of 
  these 
  

   forms, 
  as 
  well 
  as 
  of 
  many 
  of 
  the 
  Leptosporangiat^e 
  is 
  thor- 
  

   oughly 
  known 
  it 
  will 
  be 
  unsafe 
  to 
  be 
  too 
  positive 
  as 
  to 
  their 
  

   systematic 
  positions. 
  

  

  Bloomi 
  

  

  d 
  

  

  [The 
  author 
  ia 
  anxious 
  to 
  procure 
  material 
  for 
  the 
  study 
  of 
  the 
  de- 
  

   velopment 
  of 
  the 
  Ophioglosseae 
  and 
  will 
  be 
  much 
  indebted 
  to 
  any 
  of 
  the 
  

   readers 
  of 
  the 
  Gazette 
  who 
  can 
  supply 
  fresh 
  fruiting 
  specimens, 
  

   especially 
  of 
  Ophioglossum. 
  It 
  is 
  particularly 
  desired 
  to 
  have 
  fresh 
  

   spores 
  of 
  as 
  many 
  species 
  of 
  the 
  latter 
  as 
  possible.] 
  

  

  Rhizocarpeae 
  

  

  21 
  Op, 
  cit. 
  p. 
  374. 
  

  

  22 
  1 
  have 
  not 
  had 
  an 
  opportunity 
  of 
  examining 
  Gcebel's 
  investigations 
  on 
  Hymeno- 
  

   pnyiiaceifi 
  in 
  the 
  Annals 
  of 
  the 
  Botanical 
  Garden 
  of 
  Buitenzorg. 
  

  

  