BOTANY. !J55 



From tlio experiments the followiiij;' conclusions were diiiwn: 



The (leveloi)nu'nt of tlie adventitiims stalks was more i)ronounce(l the 

 greater the concentration of the salts for the same degree of humidity, 

 and for the same quantity of salts the duration of the period of growth 

 was prolonged in proportion to the amount of water at the plant's 

 disposal. The duration of the period of vegetation was also in propor- 

 tion to the amount of salts contained in the soil. 



It was observed tliat the greatest size of the stalk, shoot, and of the 

 ears corresponded to the maximum of humidity and (^oncentralion of 

 the salts in the soil. It was also observed that the yield of dry matter 

 of the whole plant and each of its parts increased with the increase in 

 the humidity and the nutritive material in the medium. 



The yield in straw and grain was twice as gieat under the highest 

 degree of humidity and the greatest nutritive content of the medium, 

 as under opposite comlitions. 



The development of the root system increased with the diminution 

 of the humidity and the concentration of the nutrient solution, while 

 the development of the stalks and leaves increased with the augmenta- 

 tion of concentration. The transpiration of the plants was proportional 

 to the humidity and the (piantity of nutriti>e material present in the 

 medium. 



The quantity of water evaporated, referred to a unit of dry matter, 

 increased with the augmentation of the (concentration of the medium 

 until the latter reached a certain limit ( t per cent), beyond which it fell. 



The percentage of water evaporated was in direct ratio to the 

 quantity contained in the soil. 



The average amount of water transpired by barley to form 1 gni, of 

 dry matter was 475 gm. 



The amount of water transi)ired in 24 hours by a surface of 100 sq. 

 cm. covered with leaves was 7.2 gm., while a free water surface evap- 

 orated 10.7 gm. 



Comi)aring the data of the last two i)aragraphs, the author concludes 

 that barley forms on an average 0.015 gm. of dry matter for 100 s{\. cm. 

 of leaved surface, so that 100 sq. cm. of the tissue of the leaves (with 

 a surface of 200 sq. cm.) furnishes 0.0,'50 gm. of dry substance in 24 



hours. — r. FIREMAN. 



The combined influence of light and medium on the devel- 

 opment of fungi, A. Lendnek {Ann. sri. nat. Hot., .scr. 6', ,-; (i^V6), J\'o. 

 1, pp. J-fiI,fi{/.s. 7).— A series of experiments with Mucor, Thamuidium, 

 Ivhi/opus, Pilobolus, Botrytis, Amblyos[)orium, and Sterigmatocystis 

 grown upon dilferent media in darkness and under red, yellow, blue, 

 violet, and clear glass are reported. The culture media used were — for 

 the liquid solutions Cohn's modilied solution, liaulin's, A'an Tieghem's, 

 Schmitz', a solution la(;king lime, and an infusion of horse dung. The 

 solid media were gelatin-])eptone and Van Tieghem's solution, horse 

 dung infusion, and liaulin's solution, to each of which 2 j)er cent agar- 

 agar was added. 



