230 EXPERIMENT STATION EECORD. 



ferent parts of the city of Leeds, comparisons being made with other regions 

 representing country and residential conditions (E. S. R., 25, p. 434). 



Three years' experiments have shown the influence of acid waters and other 

 impurities on the growth of grass. It was found that the high amounts of 

 suspended matter in town air are directly injurious to vegetation by blocliing 

 the stomata of the leaves. In addition, it exercises a considerable influence 

 by reducing the amount and intensity of solar radiation. Leaves were found 

 to have as much as 80 per cent of their stomata completely closed by the 

 matter suspended in the air. The relatively high acidity in the air as shown 

 by rain water is decidedly injurious to vegetation, but the injury is to a con- 

 siderable extent considered indirect on account of the effect of the acid on 

 the micro-organisms in the soil. The reduced yield, lower protein content, and 

 increased fiber content of grass grown under acid conditions are said to be 

 matters of serious importance for farmers in semi-urban districts. 



The influence of tobacco smoke on plants, H. Molisch (Sitsher. K. Akad. 

 Wiss. [Vierma], Math. Naturw. EL, 120 (1911), I, No. 1-2, pi). S-30, pis. 2).— 

 A detailed account is given of investigations on the effect of tobacco smoke on 

 plants, a partial report on which has been given elsewhere (E. S. R., 25, p. 225). 



In the present paper the effect of tobacco smoke on seedlings of various 

 kinds, as well as on several species of micro-organisms, is described. In the 

 case of the micro-organisms they appear less subject to injury than pea, bean, 

 and cucurbit seedlings. 



The infl.uence of tobacco smoke on plants [Rev. 06n. Sci., 22 (1911), No. 

 21, pp. 823, 82//). — An abstract is given of a report on investigations carried 

 on by Molisch in continuation of those reported above. 



In the present paper an account is given of his investigations with various 

 kinds of matured plants. These were found to react differently toward tobacco 

 smoke, some being much more susceptible than others. In the case of Boeh- 

 meria utilis it was found that the leaves of this plant when subjected to the ac- 

 tion of tobacco smoke declined from the horizontal position, until within 24 to 

 48 hours they were nearly parallel to the stem. The same movements, although 

 in a less degree, were observed in other plants. 



In a second series of experiments it was found that an abnormal production 

 of lenticels took place under the action of tobacco smoke, and in some plants 

 the formation of the lenticels was accompanied by an exudation of gum. In 

 experiments with a number of perennial plants the author found that tobacco 

 smoke caused a fall of the leaves somewhat similar to that caused by illumi- 

 nating gas. In the case of some ornamental plants the formation of antho- 

 cyanin was prevented. 



FIELD CROPS. 



[Variety and nianurial tests with cereals and root crops], 1910, P. H. 

 FouLKES, G. Balfour, and J. C. Rxjshton {Field Expts. Harper-Adams Agr. 

 Col., and Staffordshire and Shropshire Rpt. 1910, pp. 1-27, J,5, ^6, 56-68, pi. 

 1). — The work reported is mainly a continuation of that already noted (E. S. 

 R., 24, p. 728). 



In a test of 11 different fertilizer applications for meadows the highest net 

 profits for the 4 years 1907-1910 followed the use of 2* cwt. superphosphate 

 alone and with A cwt. sulphate of potash or ly cwt., nitrate of soda per acre. 

 The highest net profits for the entire 8 years of this test followed the appli- 

 cation of (1) 2 J cwt. superphosphate and I cwt. sulphate of potash, (2) 2i 

 cwt. superphosphate, and (3) 2i cwt. superphosphate, ^ cwt. sulphate of potash 

 and It cwt. nitrate of soda. 



