﻿NATURAL 
  RUBBER 
  — 
  COOK 
  411 
  

  

  1928a. 
  Dr. 
  Ridley 
  of 
  Singapore 
  and 
  the 
  beginnings 
  of 
  the 
  rubber 
  industry, 
  by 
  

  

  D. 
  Fairchild. 
  Journ. 
  Heredity, 
  vol. 
  19, 
  pp. 
  193-203. 
  

  

  1928b. 
  Beginnings 
  of 
  rubber 
  culture. 
  Journ. 
  Heredity, 
  vol. 
  19, 
  pp. 
  204-215. 
  

  

  1928c. 
  Early 
  days 
  of 
  rubber 
  experiments. 
  A 
  letter 
  from 
  Dr. 
  Ridley 
  pictures 
  

   Singapore 
  of 
  thirty 
  years 
  ago. 
  Journ. 
  Heredity, 
  vol. 
  19, 
  pp. 
  485-486. 
  

  

  1929a. 
  Rubber 
  trees 
  thrive 
  in 
  Florida 
  planting. 
  U. 
  S. 
  Dep. 
  Agr. 
  Off. 
  Rec, 
  

   vol. 
  8, 
  No. 
  5, 
  pp. 
  1, 
  8. 
  

  

  1929b. 
  Rubber 
  plants. 
  U. 
  S. 
  Dep. 
  Agr., 
  Rep. 
  of 
  Chief, 
  Bur. 
  Plant 
  Ind., 
  for 
  

   1928-1929, 
  pp. 
  26-27. 
  

  

  1930a. 
  U. 
  S. 
  hunts 
  a 
  way 
  to 
  produce 
  its 
  own 
  rubber. 
  Washington 
  Daily 
  News, 
  

   January 
  29. 
  

  

  1930b. 
  Branching 
  habits 
  of 
  the 
  Hevea 
  rubber 
  tree. 
  Science, 
  vol. 
  71, 
  pp. 
  386-387. 
  

  

  1930c. 
  Rubber 
  plants. 
  U. 
  S. 
  Dep. 
  Agr., 
  Rep. 
  of 
  Chief, 
  Bur. 
  Plant 
  Ind., 
  for 
  

   1929-1930, 
  pp. 
  31-32. 
  

  

  1930d. 
  Habits 
  of 
  Hevea 
  rubber 
  trees. 
  1st 
  Inter-American 
  Conf. 
  on 
  Agr., 
  For- 
  

   estry, 
  and 
  Animal 
  Ind., 
  Washington, 
  D. 
  C, 
  Rep. 
  of 
  Delegates, 
  pp. 
  40-41. 
  

  

  1930e. 
  The 
  debt 
  of 
  agriculture 
  to 
  tropical 
  America. 
  Bull. 
  Pan 
  American 
  Union, 
  

   vol. 
  64, 
  pp. 
  874-887. 
  (Reprinted 
  in 
  Ann. 
  Rep. 
  Smithsonian 
  Inst, 
  for 
  

   1931, 
  pp. 
  491-501; 
  also, 
  with 
  title 
  "Tropical 
  America's 
  Agricultural 
  

   Gifts," 
  in 
  Mid-Pacific 
  Mag., 
  vol. 
  42, 
  pp. 
  344-350, 
  1931.) 
  

  

  1931. 
  Rubber 
  plants. 
  U. 
  S. 
  Dep. 
  Agr., 
  Rep. 
  of 
  Chief, 
  Bur. 
  Plant 
  Ind., 
  for 
  

  

  1930-1931, 
  p. 
  24. 
  

  

  1932. 
  Study 
  of 
  supply 
  sources 
  of 
  raw 
  rubber. 
  U. 
  S. 
  Daily, 
  vol. 
  7, 
  p. 
  874. 
  

  

  1933. 
  Rubber 
  content 
  of 
  various 
  species 
  of 
  goldenrod, 
  by 
  L. 
  G. 
  Polhamus. 
  

  

  Journ. 
  Agr. 
  Res., 
  vol. 
  47, 
  pp. 
  149-152. 
  

   1935a. 
  Hevea 
  rubber 
  trees 
  in 
  Florida. 
  Science, 
  vol. 
  81, 
  p. 
  435. 
  

   1935b. 
  The 
  desert 
  milkweed 
  (Asclepias 
  subulata) 
  as 
  a 
  possible 
  source 
  of 
  rubber, 
  

  

  by 
  R. 
  E. 
  Beckett 
  and 
  R. 
  S. 
  Stitt, 
  U. 
  S. 
  Dep. 
  Agr. 
  Techn. 
  Bull. 
  472. 
  

  

  20 
  pp. 
  

   1935c. 
  The 
  Maya 
  breadnut 
  in 
  southern 
  Florida. 
  Science, 
  vol. 
  82, 
  pp. 
  615-616. 
  

  

  1937. 
  Rubber 
  production 
  from 
  Castilla 
  and 
  Hevea. 
  Science, 
  vol. 
  85, 
  pp. 
  

  

  406-407, 
  April 
  23. 
  

  

  1938. 
  Rubber 
  content 
  and 
  habits 
  of 
  a 
  second 
  desert 
  milkweed 
  (Asclepias 
  erosa) 
  

  

  of 
  southern 
  California 
  and 
  Arizona, 
  by 
  R. 
  E. 
  Beckett, 
  R. 
  S. 
  Stitt, 
  and 
  

  

  E. 
  N. 
  Duncan. 
  U. 
  S. 
  Dep. 
  Agr. 
  Techn. 
  Bull. 
  604, 
  p. 
  11. 
  

  

  1941. 
  Naming 
  the 
  cultivated 
  rubber 
  tree 
  Siphonia 
  Ridleyana. 
  Journ. 
  Washing- 
  

  

  ton 
  Acad. 
  Sci., 
  vol. 
  3, 
  pp. 
  46-65, 
  February 
  15. 
  

  

  1942. 
  Methods 
  of 
  splitting 
  Hevea 
  seedlings, 
  by 
  H. 
  F. 
  Loomis. 
  Journ. 
  Agr. 
  

  

  Res., 
  vol. 
  65, 
  pp. 
  97-124. 
  

  

  1943a. 
  More 
  rubber 
  from 
  Castilla. 
  Agriculture 
  in 
  the 
  Americas, 
  January, 
  

   pp. 
  7-9. 
  Spanish 
  trans., 
  La 
  Hacienda, 
  pp. 
  297-299, 
  July 
  1943. 
  

  

  1943b. 
  A 
  summary 
  of 
  the 
  literature 
  of 
  milkweed 
  (Asclepias 
  spp.) 
  and 
  their 
  utili- 
  

   zation, 
  by 
  A. 
  G. 
  Whiting. 
  U. 
  S. 
  Dep. 
  Agr. 
  Bibliogr. 
  Bull. 
  2, 
  41 
  pp. 
  

   Oct. 
  15. 
  

  

  