340 



e^GIENGE 



[N. S. Vol. XXXIII. No. 844 



tion. The importance of the chemical character 

 of the organic matter of the soil is considered 

 under four heads: its efl'ect on crops; its effect 

 on the bacteria and fungi of the soil; its influ- 

 ence on the physical properties of the soil, and 

 its relation chemically to the mineral ingredients 

 of the soil. By the application of the biochemical 

 methods there have been isolated in this research 

 twenty definite organic compounds thus far from 

 that portion of soil organic matter included in 

 the term humus. A chart showing the classifica- 

 tion of these compounds, as well as methods of 

 separation, was shown. The compounds com- 

 prised paraffin hydrocarbons, acids, alcohols, es- 

 ters, carbohydrates, hexone bases, pyrimidine 

 derivatives and purine bases. 



The Isolation of Creatinine from Soils: Edmund 

 C. Shoeet. 



Creatinine has been isolated from several soils 

 by the following method. An extract made by 

 shaking the soil for half an hour with 2 per cent, 

 sodium hydroxide was neutralized with acetic 

 acid and filtered. To the filtrate a small quantity 

 of dextrose was added, heated to boiling, and 

 Fehling's solution added until the precipitate 

 formed was red in color. The precipitate after 

 washing was decomposed with hydrogen sulphide 

 and the filtrate from the copper sulphide concen- 

 trated under reduced pressure. Creatinine, if 

 present in the soil, is in this filtrate together 

 with purine bases and can be separated as cre- 

 atinine zinc chloride and creatinine prepared 

 from this by treatment with lead hydroxide. The 

 creatinine was identified by the characteristic 

 crystalline appearance of the zinc chloride com- 

 pound and by the Jaffe, Weyl and Salkouski color 

 reactions. 



The Toxic Action of Organic Compounds as Modi- 

 fied by Fertilizer Salts: Oswald Scheeineb 

 and J. J. Skinnee. 



The action of fertilizer salts in restraining the 

 harmful influence of certain organic compounds 

 was studied, as well as the effect of the com- 

 pounds on absorption. The culture solutions 

 comprised all possible ratios of the three prin- 

 cipal fertilizer elements: phosphate, nitrate and 

 potassium, varying in 10 per cent, stages. 



The various fertilizer salts acted differently in 

 overcoming the respective harmful effects of the 

 toxic compounds. The mainly phosphatic fertil- 

 izers were the most efficient in overcoming the 

 cumarin effects ; the mainly nitrogenous fertilizers 

 in overcoming the vanillin effects; the mainly 

 potassie in overcoming the quinone effects. 



The cumarin depressed potash and nitrate re- 

 moval from nutrient solution more than phos- 

 phate; the quinone, on the other hand, depressed 

 phosphate and nitrate more than potash; the 

 effect of vanillin was not determined in this re- 

 gard. It is interesting to mention that dihydroxy- 

 stearie acid, which, as previously reported, ap- 

 pears to act much as vanillin did, depressed 

 phosphate and potash more than nitrate. In this 

 respect again the influence of the various harmful 

 substances was difl'erent. 



The conclusion is drawn that different toxic 

 substances produce definite effects in their action 

 on plants and that the effects are modified dif- 

 ferently by the different fertilizer salts. 



On. the Catalase Content of Tissues and Orgaiis 

 after Prolonged Fasting: P. B. Hawk, Labora- 

 tory of Physiological Chemistry, University of 

 Illinois. 



The study embraced the examination of the 

 tissues and organs of four dogs which were sub- 

 jected to periods of fasting ranging from 7 to 104 

 days. A pup one month old was subjected to a 

 7-day fast, a dog from one to two years old served 

 as the subject of the 30-day fast, whereas the 

 longer fasts were carried out upon mature ani- 

 mals. The dogs were fed a constant water ration, 

 the water being introduced by means of a stomach 

 tube. 



At the termination of the fasting periods chlo- 

 roform-water extracts of the tissues and organs 

 were prepared and their catalase values deter- 

 mined. The tissues and organs of normally nour- 

 ished dogs were subjected to a similar examina- 

 tion in order to secure data for comparative 

 purposes. 



The catalase values of the fasting tissues and 

 organs are much lower, in every instance, than 

 those of the normal tissues and organs. It was 

 also observed that the order of the tissues when 

 arranged according to their catalase content is 

 distinctly altered in the fasting animals from the 

 order in force under normal conditions. There is 

 apparently no uniformity as to the specific altera- 

 tions which take place in the catalase content of 

 animal tissues and organs under the influence of 

 fasting. The data obtained from the four fasting 

 animals under consideration are in every case 

 different from normal catalase values, but at the 

 same time these catalase values obtained from 

 fasting animals exhibit marked variations when 

 we make a comparison of the data from the four 

 animals under investigation. It is of particular 



