AGRICULTURAL BOTANY. 721 



of seeds of various ages under differently colored lights, accompanied by a table 

 showing the relative intiuence of the various colors on germination. 



The effect of certain chemical agents upon the transpiration and growth 

 of wheat seedlings, II. S. Reed (Bot. Gaz., 49 {1910), No. 2, pp. 81-100, figs. 

 9). — The present paper is intended to set forth some data upon the effect of 

 chemical compounds, mostly salts, upon the transpiration of wheat plants in 

 relation to the effect of these compounds on the growth of the plants. The data 

 [iresented were drawn from about 6,000 tests employing soils, soil extracts, 

 and salt sohitions. Many of the experiments were carried out in water cultures, 

 while others were made with soils in paraftin baskets. In most of the soil 

 experiments sodium nitrate, potassium sulphate, monocalcium phosphate, and 

 calcium carbonate were used. The experiments are described in detail. 



The author Concludes that the small amounts of the chemical agents used 

 had a definite influence upon the correlative transpiration. In the case of 

 lime and sodium phosphate the transpiration was increased, while potassium 

 salts decreased it. The effect of sodium nitrate was somewhat variable, 

 usually, however, causing a decrease in transpiration. Inorganic acids were 

 found to retard trans]»ira(iou, while the effect of organic acids was variable. 

 Pyrogallol and tannic acid resembled the action of absorbing agents in causing 

 large increases in the transpiration per unit of green growth. 



The effects produced in all cases seemed to be due to the specific action of 

 (he ions constituting any given agent. Potassium always showed its inhibiting 

 action on transpiration regardless of whether it was in combination with 

 chlorin. nitric acid, or sulphuric acid. The stimulating effect of calcium was 

 shown in a similar way. 



The influence of fermented sugar solutions on the respiration of wheat 

 germs, S. Kostytschev {Biochem. Ztschr., 23 {1909), No. 1-2, pp. 131-l-'i2). — 

 Experiments conducted by the author show that a marked increase in the pro- 

 duction of carbon dioxid, without the formation of alcohol, occurred in wheat 

 germs which were previously soaked for 1 to 2 hours in a fermented solution 

 of sugar, and therefore that this increase in carlion dioxid is not due to alco- 

 holic fermentation but to normal respiration in the wheat germs. 



The oi'igin and physiological function of pentosans in plants, C. Ravenna 

 and O. Cereser {Atti R. Accad. Lincei, Bend. CI. 8ci. Fis., Mat. e Nat., 5. ser., 

 18 {1909), II, No. 6, pp. 177-183; abs. in Jour. Chcm. 8oc. [London^, 96 {1909), 

 No. 566, II, pp. 10Jf6, 10/f7). — An investigation was made of beans in which it 

 was found that there was no marked variation in the quantity of pentosans 

 observed during the period of activity of the chlorophyll. During the night, 

 however, when chlorophyll action was diminished, the variations were con- 

 siderable, sometimes there being increases while at other times there was a 

 diminution in the amount present. When the carbohydrate food consisted 

 wholly of glucose, administered to the leaves, the amount of pentosans was 

 found to increase greatly, especially when the plants were kept in the light. 

 Whenever the chlorophyll function of the leaves was prevented for a long 

 period the amount of pentosans was found to diminish. 



The conclusion is drawn that the simple sugars rather than the complex 

 carbohydrates exert an influence on the formation of pentosans which serve 

 as a I'eserve material when the plant has exhausted its more readily utilizable 

 substances. 



Are amins assimilable by higher plants? M. Molliaed {Compt. Rend. 

 Acad. Hci. [Paris], l.',9 {1909). No. 17. pp. 685-687: ahs. in Jour. Chem. 8oc. 

 [London], 96 {1909), No. 566, II, p. 10.'t6).—l\i a previous publication (E. S. R., 



42556— No. 8—10 3 



