F. KiDD AND C. West 15 



doubt that the action of sulphuric acid is further strikingly effective in 

 increasing the rate of growth during at least the first three months of 

 the plant's life." This observation of Goodspeed's is supported by results 

 recorded by F. Plate (29). Working with seeds of Avena sativa Plate noticed 

 that after treatment with various inorganic acids the germination of 

 the seeds was greatly accelerated, and that the plants produced from the 

 treated seeds were more vigorous than the controls. He observed that 

 the reserve materials were exhausted in the case of the acid-treated 

 seeds in 10 days as against 15 days in the case of untreated seeds. 



The effect of hydrocyanic acid gas upon dry and moist seeds re- 

 spectively has been investigated by Townsend (34 ami 35) ; the necessity 

 for the investigation arose from the rapidly increasing use of this gas in 

 the destruction of insect pests infesting stored grains and other seeds 

 and also for the fumigation of greenhouses. Townsend found that dri/ 

 seeds of corn, wheat, beans and clover might remain without injury to 

 their germinating power for several weeks in an atmosphere containing 

 a greater concentration of hydrocyanic acid gas than is required to kill 

 quickly insect life. The germination of these seeds was found to be 

 accelerated after this treatment and the rate of growth of the seedlings 

 to be above the normal. 



The action of boric acid upon the germination and subsequent 

 development of seeds has been investigated by Morel (24). This author's 

 results showed that brief treatment with boric acid at the time of 

 germination produced a persistent deleterious effect upon haricot beans. 

 The results noted about 7 weeks after sowing in ordinary soil are given 

 in the following table : 



Table X. 



Treatment of the seeds pre- 

 vious to sowing in soil 



Strength of Period of Results noted in the plants after 7-8 weeks' 



acid used soaking growth 



1 "o boric acid 15 mins. Showed no appreciable difference from the controls 



1 % „ 30 „ Differed from the controls only in the colour of their leaves 



which were of a less clear green 

 1 % ,, 60 ,, The leaves of these plants were small and yellowish 



It is seen that treatment of the dry seed with a 1 per cent, solution 

 of boric acid even for | hour has a clearly visible effect upon the resulting 

 plant during its whole course of growth. 



In a similar series of experiments with seeds which had been pre- 

 viously immersed for 6 hours in water in order to render them more 

 permeable to the acid solution, the following results were obtained; 



