Physiologie. 269* 



DixON , H. H. , Observations on the Temperature of 

 the Subterranean Organs of Plants. (Trans. Royal 

 Irish Acad. Vol. XXXII. Sect. B. 1903. Pt. II.) 



During active growth large roots, bulbs, and other sub- 

 terranean organs show a temperature somewhat higher than 

 their surroundings — an average excess oi about — .06° C. 

 being usual. When active growth ceases no appreciable eleva- 

 tion of temperature can be detected. The spontaneous 

 diurnal rise in temperature described for aerial organs appears 

 to be wanting, though owing to the diurnal periodic Variation 

 in temperature of the surroundings which in turn induces a 

 change in respiratory activity, a periodic rise may occur. 



E. Drabble (London). 



Green, A. B., A note on the Action of Radium on 

 Mi c r o o rgan isms. (Proc. Royal. Soc. London. Vol. LXXIII. 

 No. 494. May 1904.) 



Experiments on Vaccine show that the specific organism is 

 killed after 22 hours exposure to Radium, and the Vaccine then 

 excites no visible irritation on inoculation into a calf. The 

 extraneous organisms of the Vaccine — 6\ pyogenes aureus, 

 S. pyogenes albus, S. cereus flavus, and 6". cereus albus, were 

 killed after a slightly shorter exposure than that necessary to 

 kill the specific germ. 



Spore-containing bacteria are by far the most resistent, 72 

 hours exposure being required to destroy them. 



After exposure to Radium-emanations for from 24 to 120 

 hours micro-organisms themselves may exhibit the phenomenon 

 of radio-activity. It is at present uncertain whether living 

 micro-organisms can acquire this property, but those killed by 

 the action of Radium can do so. E. Drabble (London). 



LIVINGSTON, B. E., Physical Properties of Bog Water. 

 (Bot. Gaz. Vol. XXXVII. May 1904. p. 383—385.) 



Eight samples of bog water, taken from widely separated 

 localities, showed, by their freezing points, almost no increase 

 in osmotic pressure over that of ordinary lake or river water. 

 Concludes that bog waters therefore do not have an appre- 

 ciably higher concentration of dissolved substances than do 

 the streams and lakes of the same region, hence it must be 

 the chemical nature of the very small amounts of dissolved 

 substances which determines any peculiar property of bog 

 water in preventing ordinary swamp plants from growing 

 therein. H. M. Richards (New York). 



Snyder, H., The Water Soluble Plant Food of Soils. 

 (Science. Vol. XIX. May 27, 1904. p. 834—835.) 



A criticism of Bulletin No. 22, Division of Soils, U. S. 

 Dept. of Agriculture. Concludes that the figures in the bulletin 



