BOTANY. 823 



From the tabulated material it appears that seeds of Pbaseolus aiid 

 Vicia will not germinate in an atmosphere containing 80 per cent of 

 nitrous oxid. Seedlings of these plants will remain active for more 

 than 24 hours in an atmosphere of commercial nitrous oxid, but no 

 growth will take place. In some cases shoots exhibited accelerated 

 growth after being kept in an atmosphere of free nitrous oxid, or where 

 the amount of gas ranged from 25 to 100 per cent, but no growth could 

 be detected during the experiments. Aquatic plants showed consider- 

 able increased growth in solutions saturated with nitrous oxid. Seeds 

 germinated readily in atmospheres of free oxygen, but seedlings kept 

 in such an atmosphere did not grow as rapidly as those in ordinary air. 

 Growing shoots kept in an atmosphere containing 25 to 100 per cent of 

 free oxygen remained unchanged for as long a period as 20 days, but 

 upon removal slowly perished. 



Vapors of ammonia when used in quantities not exceeding 1 to 

 24,000 are not harmful to the germination of seeds of Phaseolus. Seeds 

 exposed for 9 days in glass chambers containing from 1 to 24,000 and 1 

 to 32,000 parts of ammonia germinated as freely as in the control 

 experiments. On the other hand the seed of Vicia faba is very sus- 

 ceptible to the influence of this vapor, and specimens kept for 9 days 

 in 1 to 28,000 of ammonia failed to germinate. Both the Phaseolus 

 and Yicia seed kept for 9 days in an atmosphere containing 1 to 20,000 

 of ammonia failed to germinate. The growth of young seedlings of 

 maize kept for 48 hours in a moist chamber containing 1 to 20,000 of 

 ammonia was seriously retarded. Resting bulbs are not affected by 

 being kept in atmospheres containing 1 part of ammonia in 5,000. 

 Chloroform and ether have a very similar effect upon growth. Seed- 

 lings of maize kept in a moist chamber contaiuing 1 to 10,000 parts of 

 chloroform or ether showed a marked acceleration in growth after being 

 removed from the moist chamber. An atmosphere containing 1 to 5,000 

 greatly retarded growth. Resting bulbs and growing shoots are 

 equally susceptible and are killed after being exposed for 10 to 20 days 

 in atmospheres containing 1 to 10,000" of either chloroform or ether. 

 The carbon bisulphid in extremely small amounts proved injurious to 

 all growing plants, although it was inoperative on resting seeds. 



When used in quantities not exceeding 1 to 10,000, alcohol has no 

 effect upon the growth of seedlings. If larger quantities are used the 

 growth is retarded and the seedlings killed. Resting bulbs kept iu an 

 atmosphere containing 1 to 500 and 1 to 1,000 parts of alcohol grew, 

 but the floral orgaus were dwarfed and the flower buds remained 

 unopened. 



The toxic action of a certain group of substances, R. 11. True 

 (Proc. Amer. Assoc. Adv. Sci., 47 (1898), p. 410).— The author states that 

 common salt and potassium nitrate have long been regarded as essen- 

 tially lacking in toxic action, and operate only through their osmotic 

 activity. In his experiments cane sugar was assumed to be a purely 



