﻿CHAPTER 
  XVII 
  

   MOSSES, 
  LIVERWORTS, 
  AND 
  FERNS 
  

  

  248. 
  Introductory. 
  The 
  mosses 
  belong 
  to 
  the 
  second 
  great 
  

   division 
  of 
  the 
  plant 
  kingdom, 
  the 
  bryophytes, 
  which 
  means 
  

   "moss 
  plants." 
  All 
  small, 
  green 
  plants 
  are 
  commonly 
  called 
  

   mosses, 
  but 
  when 
  we 
  discover 
  what 
  kinds 
  of 
  plants 
  mosses 
  

   are, 
  we 
  shall 
  see 
  how 
  incorrect 
  such 
  a 
  general 
  use 
  of 
  the 
  

   term 
  is. 
  The 
  bryophytes 
  also 
  include 
  another 
  group, 
  the 
  liver- 
  

   worts, 
  which 
  are 
  peculiar 
  and 
  infrequently 
  noticed 
  plants. 
  

   The 
  mosses, 
  on 
  the 
  contrary, 
  are 
  extremely 
  abundant 
  and 
  

   grow 
  in 
  almost 
  all 
  kinds 
  of 
  places. 
  The 
  ferns 
  (pteridophyteb, 
  

   which 
  means 
  "feather 
  plants," 
  or 
  "fern 
  plants") 
  constitute 
  

   the 
  third 
  great 
  division 
  of 
  the 
  plant 
  kingdom 
  and 
  will 
  be 
  con- 
  

   sidered 
  after 
  the 
  bryophytes. 
  It 
  is 
  so 
  much 
  easier 
  to 
  get 
  clear 
  

   notions 
  of 
  the 
  bryophytes 
  by 
  a 
  study 
  of 
  the 
  mosses, 
  that 
  we 
  

   shall 
  give 
  our 
  chief 
  consideration 
  to 
  them, 
  rather 
  than 
  to 
  the 
  

   liverworts, 
  which 
  are 
  simpler 
  in 
  some 
  ways 
  but 
  less 
  common 
  

   and 
  less 
  easily 
  studied 
  than 
  mosses. 
  

  

  249. 
  The 
  moss 
  plant. 
  Careful 
  observation 
  of 
  any 
  common 
  

   moss 
  will 
  enable 
  one 
  to 
  see 
  that 
  it 
  has 
  green, 
  leaf 
  -like 
  struc- 
  

   tures 
  arranged 
  around 
  a 
  very 
  small 
  stem. 
  Sometimes 
  also 
  

   there 
  appears 
  upon 
  this 
  leafy 
  stem 
  a 
  slender 
  stalk 
  with 
  a 
  

   swollen, 
  pod-like 
  tip, 
  or 
  capsule 
  (fig. 
  203, 
  (7). 
  In 
  this 
  tip 
  many 
  

   simple 
  asexual 
  spores 
  are 
  formed, 
  and 
  if 
  we 
  follow 
  the 
  life 
  

   round 
  of 
  the 
  moss, 
  beginning 
  with 
  the 
  development 
  of 
  one 
  of 
  

   these 
  spores, 
  we 
  shall 
  get 
  a 
  good 
  notion 
  of 
  the 
  nature 
  of 
  the 
  

   structures 
  of 
  the 
  moss 
  plant. 
  

  

  I 
  'poii 
  the 
  germination 
  of 
  the 
  asexual 
  spore 
  there 
  grows 
  

   from 
  it 
  a 
  filament, 
  or 
  thread, 
  which 
  looks 
  so 
  much 
  like 
  the 
  alg;e 
  

   that 
  it 
  is 
  often 
  extremely 
  dillicult 
  to 
  distinguish 
  it 
  from 
  them. 
  

  

  202 
  

  

  