454 



strictly forbidden and the seeds must be disinfected with Bordeaux 

 mixture or some sueh disinfectant. One planter having alleged that 

 such disinfection would kill the seed, M. Morange' made a series of 

 experiments with bichloride of mercury, and copper sulphate with 

 the following result : 



1. Bichloride of Mercury I per 1,000 



A. Seeds washed after treatment Proportion of seeds 

 which germinated after 30 days ... 70% 



B. Seeds not washed ... ... 68% 



2. Bichloride 2 per 1,000 



washed ... ... 84 



not washed ... ... 90 



3. Sulphate of copper I per cent, 



washed after ... 62% 



not washed ... ... 52% 



4. Sulphate of copper 5 per cent. 



washed ... ... 68% 



not washed ... ... 62% 



Check experiment. Seeds washed in pure water gave 78, 

 and 70% germinated after 30 days 



The seeds were put in the disinfectant for half an hour. 



Except in one case there is a slight proportion of larger germina- 

 tion in the washed over the unwashed seeds, and there is a fall off in 

 germination in the seeds treated with copper sulphate but not a very 

 large one compared with the check experiments. 



Another experiment was made by M. Belland — 400 seeds were 

 plunged in water and left for half an hour; all germinated 



500 were put in a solution of I per cent, of copper sulphate for 

 half an hour and continuously stirred round (brassees) ener- 

 getically for half an hour. Of these only 38 germinated. 



500 were similarly treated with a solution of bichloride of mer- 

 cury I per 1,000, only fifty four germinated. 



M. Morange made also an experiment of the same nature. 



Five hundred seeds were sown dry without washing and 285, 

 i. e. 56.8 per cent, germinated in a month. 



Another lot were stirred in plain water more carefully, of these 

 213. or 42. 6 percent, germinated. 



Another lot was stirred i.i copper sulphate solution 2 per cent 

 and 291 or 58. 2 per cent, germinated. 



A fourth lot were stirred in Bichloride of Mercury at 2 per 

 1,000, of these 285 or 59 per cent. grew. 



