﻿213 
  

  

  FOODS 
  IN 
  PLA 
  

  

  UNIVERSITY 
  HIGH 
  SCHOOL 
  

   LIBRARY 
  

  

  ARBOR. 
  MICHIC/&J 
  

  

  51. 
  Saprophytes. 
  In 
  general, 
  the 
  seed 
  plants 
  which 
  are 
  

   saprophytes 
  occur 
  only 
  in 
  the 
  forest 
  or 
  under 
  shrubs. 
  It 
  is 
  in 
  

   such 
  situations 
  that 
  plants 
  find 
  a 
  most 
  abundant 
  supply 
  of 
  

  

  humus, 
  or 
  decaying 
  organic 
  matter. 
  Com- 
  

   plete 
  saprophytes 
  - 
  - 
  that 
  is, 
  those 
  which 
  

  

  FIG. 
  33. 
  A 
  single 
  Indian 
  

  

  pipe 
  plant 
  (Monotropa 
  

  

  uniflora) 
  

  

  Note 
  the 
  slender 
  stem 
  and 
  

   reduced 
  leaves 
  

  

  FIG. 
  34. 
  Clover 
  dodder, 
  parasitic 
  on 
  red 
  clover 
  

  

  A, 
  habit 
  sketch 
  of 
  part 
  of 
  the 
  parasite 
  and 
  the 
  

   host; 
  B, 
  portion 
  of 
  stem 
  of 
  the 
  dodder, 
  showing 
  

   protuberances 
  from 
  which 
  haustoria 
  pass 
  into 
  the 
  

   stem 
  of 
  the 
  host 
  ; 
  C', 
  a 
  single 
  flower 
  of 
  the 
  dodder. 
  

   B 
  and 
  C 
  considerably 
  magnified. 
  Modified 
  after 
  

   "Flora 
  Danica" 
  

  

  cannot 
  exist 
  without 
  an 
  abundant 
  supply 
  of 
  soluble 
  organic 
  

   matter 
  in 
  the 
  soil 
  or 
  sub-stratum 
  - 
  - 
  are 
  always 
  pale, 
  or 
  even 
  

   white, 
  from 
  partial 
  or 
  complete 
  absence 
  of 
  chlorophyll 
  (fig. 
  32). 
  

   Their 
  leaves 
  are 
  small 
  and 
  scale-like 
  (fig. 
  33). 
  Their 
  roots 
  

   are 
  usually 
  short 
  and 
  have 
  little 
  tendency 
  to 
  branch. 
  Some 
  

  

  