﻿MOSSES, 
  LIVERWORTS, 
  AND 
  FERNS 
  281 
  

  

  GROUP 
  B. 
  BRYOPHYTES 
  

  

  CLASS 
  I. 
  HEPATIC,*: 
  (liverworts). 
  Genus 
  used 
  as 
  illustration-^ 
  

  

  Marchantia 
  

   CLASS 
  II. 
  Musci 
  (mosses). 
  Leading 
  genera 
  used 
  as 
  illustrations 
  - 
  

  

  Atrichum 
  and 
  Sphagnum 
  

   GROUP 
  C. 
  PTERIDOPHYTES 
  

  

  CLASS 
  I. 
  FILICIN.-E 
  (the 
  true 
  ferns). 
  Leading 
  genera 
  used 
  as 
  illus- 
  

   trations 
  Pteris 
  (the 
  bracken 
  fern), 
  Adiantum 
  (the 
  maidenhair 
  

  

  fern), 
  Onoclea 
  (the 
  sensitive 
  fern, 
  or 
  oak 
  fern) 
  

   CLASS 
  II. 
  EQUISETIN.C 
  (horsetails, 
  or 
  scouring 
  rushes). 
  Genus 
  used 
  

  

  as 
  illustration 
  Equisetum 
  (the 
  only 
  living 
  genus 
  of 
  the 
  class) 
  

   CLASS 
  III. 
  LYCOPODIN.E 
  (club 
  mosses 
  or 
  ground 
  pines). 
  Genus 
  used 
  

  

  as 
  illustration 
  Lycopodium 
  (one 
  of 
  the 
  three 
  living 
  genera 
  of 
  

  

  the 
  class) 
  

  

  PROBLEMS 
  

  

  1. 
  Of 
  what 
  importance 
  are 
  mosses 
  as 
  soil 
  formers? 
  

  

  2. 
  What 
  is 
  the 
  significance 
  of 
  the 
  radial 
  arrangement 
  of 
  the 
  leaves 
  

   of 
  the 
  moss 
  plants 
  ? 
  

  

  3. 
  Why 
  is 
  it 
  important 
  to 
  the 
  plants 
  that 
  the 
  asexual 
  spores 
  of 
  

   mosses, 
  liverworts, 
  and 
  ferns 
  should 
  have 
  wide 
  distribution 
  ? 
  

  

  4. 
  In 
  what 
  sense 
  is 
  it 
  true 
  that 
  the 
  vascular 
  tissue 
  exemplified 
  in 
  

   ferns 
  means 
  about 
  the 
  same 
  to 
  the 
  plant 
  kingdom 
  as 
  the 
  vertebral 
  

   column 
  (backbone) 
  means 
  to 
  the 
  animal 
  kingdom 
  ? 
  

  

  5. 
  Why 
  is 
  it 
  that 
  peat-bog 
  moss 
  is 
  good 
  material 
  for 
  covering 
  the 
  soil 
  

   of 
  potted 
  plants 
  and 
  for 
  packing 
  fragile 
  articles 
  for 
  shipping 
  ? 
  

  

  6. 
  In 
  what 
  ways 
  may 
  ferns 
  be 
  propagated 
  vegetatively 
  ? 
  How 
  do 
  

   florists 
  propagate 
  their 
  ferns? 
  

  

  7. 
  What 
  structures 
  of 
  ferns 
  help 
  to 
  explain 
  the 
  fact 
  that 
  most 
  ferns 
  

   thrive 
  best 
  in 
  damp 
  and 
  shaded 
  regions 
  ? 
  

  

  8. 
  In 
  museums 
  that 
  you 
  have 
  visited 
  what 
  fossil 
  evidences 
  are 
  there 
  

   that 
  ferns 
  lived 
  during 
  former 
  ages 
  ? 
  

  

  