January, 1918 C. U. C. P. ALUMNI JOURNAL 



KBSTRKCTS 



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Conducted by Prof. George C. Diekman. 



Constituents of Ginger 

 H. Nomura, in Chew. Soc. Trans., 1917, in, describes a new constituent 

 of ginger, which he names zingerone, and which he states is a ketone (4-hydroxy- 

 5-methyloxyphenylethyl methyl ketone). The powdered ginger is extracted with 

 ether, when a solution containing a ketone-phenol like substance is obtained. This 

 is isolated by treatment with solution of sodium hydroxide, and subsequent liber- 

 ation by carbon dioxide. Various impurities are removed by treatment with so- 

 lution of sodium carbonate. The pure substance is finally obtained by distillation 

 under reduced pressure. Zingerone forms colorless crystals, which melt at 40° 

 to 41° C. It forms characteristic combinations with sodium bisulphite, a benzoyl 

 derivative, an acetyl derivative, a methyl and an ethyl ether. 



Bacteria and Fungi in Plants 

 Experiments carried on by E. Berthold were made with a view to determin- 

 ing the depth to which various bacteria and fungi were able to penetrate plant 

 tissues and the length of time they remained active. The tissues of herbaceous 

 plants and the sap and heartwood of woody plants, were found to be free of bac- 

 teria under normal conditions. It was also found that in cases where wood is 

 attacked by fungi, that their presence could be demonstrated, but that bacteria 

 were not present at the same time. A section of a woody plant when placed in 

 water became infected with bacteria and the spores of fungi were also absorbed, 

 the penetration depending upon the length of the vessels in the section. Bacteria 

 when injected into living wood or into tissues of living herbaceous plants were 

 found to remain alive for periods as long as ten months, but development was 

 not observed. The author states definitely that only dead-tissue can be used tq 

 promote bacterial growth. 



Toxic Value of Arsenates 



I 



Tests having for their object the determination of the toxic action of sohu 

 tions of various arsenates upon the common tent caterpillar (Malacosorqa plu- 

 vialis) were conducted by A. \.. I.ovelt and Iv. il. Robinson, anil are described 

 in the Journ. Agric. Res., 1917, 10. The authors found that lead hydrogeji ar- 

 senate was more efficient and active than solutions of calcium or basic lead arsen- 

 ates of the same concentration. It was found that the quantity of arsenic re= 

 tained by insects feeding upon plant parts sprayed with arsenic solutions, varies 

 with the kind of arsenate used. While it was found that in the case of basic lead 

 arsenate there is a rajiid elimination, in the case of the lead hydrogen arsenate it 

 was shown that most of this is retained in the tissues. Field tests using sprays 

 of calcium arsenate and calcium ammonium arsenate demonstrated that both of 



