BOTANY. 825 



chlorate gave a decrease of from 3 to 50 per cent. Where only 0.75 

 per cent of perchlorate was used the poisonous effect was evident and 

 the crop 3 per cent smaller than on the check plats. The plats treated 

 with perchlorates without nitrates gave only half a crop, although the 

 plants did not appear as badly injured as did those of some of the other 

 plats. In November some plats were treated with sodium perchlorate, 

 others with potassium perchlorate mixed with nitrates. The injurious 

 effect was soon apparent, even when onl}'' O.Oi per cent of sodium per- 

 chlorate had been used, but in this case the plants eventually outgrew 

 the effects of the poison. When 2 to 3 per cent of sodium perchlorate 

 was used many of the plants were killed. The effect of the potassium 

 perchlorate was ultimatel}' outgrown, even when as much as 3 per cent 

 of it had been mixed with nitrate of soda. 



Experiments on turnips followed b}" rye showed that turnips are 

 poisoned by perchlorates and that more than one crop ma}' be injured 

 by an application of nitrate of soda containing perchlorate. Oats and 

 corn are also liable to injury, but do not suffer as seriousl}^ from it as 

 rye. — h. m. pieteks. 



Electricity in plant culture {Nature, 61 {1900), No. 1590, j)- 602). — 

 A brief account is given of experiments conducted in Russia by 

 Spyeshneff' and Kravkoff. The former reported results of the well- 

 known experiments with electrified seeds, in which he ascertained that 

 such seeds germinated more rapidly and gave yields from 2 to 6i times 

 higher than seeds not subjected to the preliminary electrification. In 

 another series of experiments copper and zinc plates were placed verti- 

 cally in the soil and connected by wires. Potatoes and roots grown 

 in the space between gave crops 3 times heavier than those grown in 

 the test plat at the side. 



In a third series of experiments by this author wooden posts were 

 planted about 10 yards apart and provided at their tops with meta,! 

 aigrettes connected by wnres, so as to cultivate his plants under a net- 

 work of wires. Among the most striking results obtained in this experi- 

 ment was in the ripening of barley, which was accelerated 12 days. 



The other investigator undertook a series of laboratory experiments 

 upon bags of soil submitted to electric currents. The temperature of 

 the soil was raised by these currents. Its moisture at first decreased, 

 but afterwards increased to a considerable degree, and finally it is 

 claimed the amount of vegetable matter in the soil was increased by 

 the electric current. 



On the embryo of mummy -wheat and barley, E. Gain {Cornpt. 

 Rend. Acad. Scl. Pari^, 130(1900), No. 21^, pp. i6l^^-i^/^6').— An account 

 is given of a number of investigations on specimens of wheat and Ijar- 

 ley which were taken from ancient tombs and are probably from •1,000 

 to 6,000 years old. Transverse and longitudinal sections were made 

 of a large number of grains to ascertain what changes they had under- 



17622— No. 9 3 



