﻿INDEX 
  

  

  365 
  

  

  Plant 
  fibers, 
  312-314 
  

  

  Plant 
  geography, 
  197 
  

  

  Plant 
  industries, 
  *308-332 
  

  

  Plant 
  lice, 
  328, 
  330 
  

  

  Plantain, 
  flowers 
  of, 
  152* 
  

  

  Plant-breeding 
  rules, 
  190, 
  191 
  

  

  Plasmopara, 
  239*, 
  261 
  

  

  Plastid, 
  37* 
  

  

  Pleurococcus, 
  221, 
  222*, 
  223, 
  249, 
  260 
  

  

  Plum, 
  black 
  knot 
  of, 
  247 
  

  

  Plums, 
  187* 
  

  

  Plumule, 
  158*, 
  160*, 
  102* 
  

  

  Poison 
  ivy, 
  73* 
  

  

  Pollarding, 
  98* 
  

  

  Pollen, 
  15, 
  128*, 
  129*, 
  130*, 
  134*, 
  

  

  135* 
  

  

  Pollen, 
  discharge 
  of, 
  128*, 
  129* 
  

   Pollen 
  chamber, 
  129* 
  

   Pollen 
  grain, 
  germination 
  of, 
  135*, 
  

  

  301*" 
  

  

  Pollen 
  sac, 
  129* 
  

   Pollen 
  tubes, 
  16, 
  135*, 
  136*, 
  291*, 
  

  

  300 
  

  

  Pollen-carrying, 
  139 
  

   Pollen-carrying 
  apparatus, 
  146*, 
  150* 
  

   Pollination, 
  *134-154, 
  290 
  

   Pollution 
  of 
  water 
  supply, 
  229 
  

   Polyporus, 
  234*, 
  235*, 
  261 
  

   Pond 
  lily, 
  78* 
  

  

  Pondweed, 
  section 
  of 
  stem 
  of, 
  85* 
  

   Potato, 
  87*, 
  88*, 
  145* 
  

   Potato 
  blight, 
  240*-242 
  

   Preservation 
  of 
  fruits, 
  208, 
  209 
  

   Pressure 
  of 
  water, 
  24 
  

   Privet, 
  branching 
  of, 
  97* 
  

   Propagation 
  by 
  cuttings, 
  90 
  

   Propagation 
  by 
  roots, 
  32* 
  

   Propagation 
  by 
  seeds, 
  *161-171 
  

   Proteins, 
  17, 
  39, 
  43, 
  159, 
  183, 
  184 
  

   Protonema, 
  263*, 
  266 
  

   Protoplasm, 
  21, 
  22 
  

   Protoplast, 
  21 
  

   Pruning, 
  317*, 
  318* 
  

   Pruning 
  due 
  to 
  shade, 
  77-79 
  

   Pteridophytes, 
  261, 
  *269-281 
  

   Pteridophytes, 
  classification 
  of, 
  281 
  

   Pteridophytes, 
  evolution 
  of, 
  306 
  

   Pteris, 
  271* 
  

   Ptomaines, 
  209 
  

   Public 
  health, 
  212-218 
  

   Puccinia, 
  255*, 
  256, 
  261 
  

   Puffball, 
  259*, 
  260 
  

   Pulvinus, 
  77 
  

  

  Q,uercus, 
  194, 
  195*, 
  196 
  

  

  Radial 
  symmetry, 
  129 
  

  

  Easpberry, 
  89*, 
  157*, 
  171* 
  

  

  Receptacle, 
  126* 
  

  

  I!. 
  >d 
  algse, 
  232*, 
  233, 
  261 
  

  

  Red 
  clover, 
  leaf 
  of, 
  77* 
  

  

  Redwood, 
  294 
  

  

  Reindeer 
  moss, 
  251 
  

  

  Reproduction, 
  sexual, 
  in 
  flowering 
  

  

  plants, 
  *134-137, 
  *289-292, 
  *299- 
  

  

  303 
  

  

  Reproduction, 
  of 
  bacteria, 
  201-203 
  

   Reproduction, 
  by 
  portions 
  of 
  stem, 
  

  

  *87-92 
  

  

  Reserve 
  food 
  in 
  seeds, 
  158, 
  159, 
  165 
  

   Resin 
  duct, 
  285* 
  

   Respiration, 
  46, 
  47 
  

   Resting 
  buds, 
  94 
  

   Rest 
  period 
  in 
  seeds, 
  162 
  

   Rhizoids, 
  236 
  

   Rhizome. 
  Sec 
  Rootstock 
  

   Rhizopus, 
  260 
  

   Rhodophycese, 
  260 
  

   Ring, 
  annual, 
  12*, 
  66 
  

   Rise 
  of 
  water 
  in 
  stems, 
  42, 
  43 
  

   Rockweed, 
  231* 
  

   Rolling, 
  177 
  

   Root, 
  8*, 
  9, 
  10*, 
  11* 
  

   Root, 
  fleshy, 
  45* 
  

   Root, 
  section 
  of, 
  11*, 
  20* 
  

   Root 
  absorption, 
  9 
  

   Root 
  climbers, 
  73*, 
  74 
  

   Root 
  hairs, 
  9, 
  10*, 
  11*, 
  21* 
  

   Root 
  system, 
  25 
  

   Root 
  tubercles, 
  *203-207 
  

   Rootcap, 
  20 
  

   Roots, 
  aerial, 
  30*, 
  31 
  

   Roots, 
  air 
  requirements 
  of, 
  26*-28 
  

   Roots, 
  anchorage 
  by, 
  8*, 
  9 
  

   Roots, 
  earth, 
  25-29 
  

   Roots, 
  effects 
  of, 
  on 
  soil, 
  26, 
  27 
  

   Roots, 
  parasitic, 
  31 
  

   Roots, 
  pull 
  of, 
  25, 
  26 
  

   Roots, 
  reproduction 
  by, 
  32* 
  

   Roots, 
  storage 
  of 
  food 
  and 
  water 
  in, 
  

  

  45* 
  

  

  Roots, 
  structure 
  of. 
  20*, 
  21* 
  

   Roots, 
  water, 
  29*-31 
  

   Roots, 
  water-lifting 
  by, 
  24 
  

   Rootstock, 
  86*, 
  87, 
  271, 
  272* 
  

   Root-tubercle 
  bacteria 
  *205~207 
  

   Roquefort 
  cheese, 
  245 
  

   Rose, 
  leaf 
  bud 
  of, 
  94* 
  

   Rosette 
  plants, 
  72*, 
  73 
  

   Runners, 
  90 
  

   Run-off, 
  119, 
  120 
  

  

  