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GERMINATION OF PARA-RUBBER SEED. 



The subject of the germination of the seeds of the Para rubber is 

 studied by Mr. Vernet in " Le Contchou et laGutta percha" of May 1908 

 page 1945, who has made a series of experiments on the growth -of the 

 seedling. 



He put a hundred fresh seeds in a basin of earth with the micro- 

 pyle end upwards and the hilum downwards, covered them with a wet 

 cloth and watered it daily. 



In his first experiment, the first seed pushed out its rootlet at the 

 end of seven days, the last on the thirty-third day. The greatest num- 

 ber germinated between the 10th and 27th days. Ninety one per cent 

 germinated. Occasionally seeds germinate in the capsule and if this 

 goes on for some time the stalk and rootlet become twisted and the 

 plant is spoiled. 



He then made some experiments with however only 20 seeds by 

 putting them in powdered charcoal in a hermetically sealed box, for 

 periods of from 1 to 40 days, then germinating them as before. 



The check experiment out of 20 seeds gave 18 germinations. Those 

 enclosed in the box of charcoal for 6, 10, 12, and 14 days gave a germi- 

 nation of 80 per cent. After 16 days 70 per cent, 18 days 50 per cent 

 20 days 55 per cent, 20 days 25 per cent, 29 days 30 per cent, 35 days 

 25 per cent, and 40 days 20 per cent. 



From this he concludes that dry charcoal is a bad perservative. 

 In damp charcoal after 7 days he found the seeds had germinated and 

 they are apt to be spoilt on the way if sent packed up thus. 



He recommends that the seeds should be packed in hermetically 

 sealed vessels after being exposed for 24 hours to the air to get rid of 

 the moisture on them. The boxes should be small in order to prevent 

 heating. The small boxes should be packed in strong cases to protect 

 them against variations of temperature. 



He does not give the dimensions of the hermetically sealed cases, 

 but unless they were very small the danger from heating would be 

 excessive, and some packing material is certainly requisite. Seeds do 

 not so far as I have seen heat with a sufficient supply of any packing 

 material such as charcoal, but as a rule without any they heat and are 

 spoiled in a couple of days. M. Vernet does not seem to have seen the 

 accounts of packing and export of seeds published in the Bulletin. 



We have not yet found a superior packing material to the charcoal 

 of rice husks for long distance sendings. In using powdered charcoal 

 for packing much depends on the amount and equal distrubution 

 of the moisture in it. It must not be too much or too little, and 

 charcoal powder is not easy to damp equally all through, but very 

 good results have been obtained by its use for long distance travelling. 

 The only really reliable experiments in this direction are to be made by 

 actually sending seed through the post freight. The rise and fall 

 of temperature while passing through hot and cold regions may affect 

 a case even hermetically sealed, as also may the rise of temperature in 

 the hold of the ship, 



As an example of the effects of alteration of temperature in a 

 hermetically sealed case, may be cited the fact that many years ago I 

 commenced sending home dried plants for herbarium specimens in a 



