president's addr'ess. 11 



The year's work of the Society's research-statf may be sum- 

 marised as follows: — Dr. R. Greig-Smith, Macleay Bacteriologist 

 to the Society, contributed two papers during the Session, which 

 have already appeared in Parts i.-ii. of the Proceedings for 1917. 

 One, the fifteenth of his series of contributions to a knowledge 

 of soil-fertility, dealt especially with the action of certain micro- 

 organisms upon the number of bacteria in the soil; and the other 

 was descriptive of an improvement in the technique of the single 

 cell cultivation of yeast. He also completed the sixteenth 

 of the series already alluded to, which is concerned with the 

 search for toxin-producers. Certain soil-bacteria, moulds, and 

 amcebi«, all reasonably supposed to be capable of furnishing sub- 

 stances of a toxic nature, have been grown in various media and 

 under varying conditions, and, in all cases, the signs of toxicity, 

 which become manifest, can be attributed to an alteration in 

 in the reaction of the media. The effect of reaction is quite of 

 a different order from the evidence of toxic action obtained in 

 former researches. 



Dr. Petrie, Linnean Macleay Fellow of the Society in Bio- 

 chemistry, contributed three papers, which are contained in Part 

 i. of last year's Proceedings. One of them was a continuation of 

 his investigations on the occurrence of hydrocyanic acid in plants 

 (Part iii.), and furnished a record of some new cyanogenetic 

 plants. The other two treated, in an exhaustive manner, of the 

 chemistry of the Duboisias, and the alkaloids of Duboisia Leich- 

 hardtii. Additional subjects which occupied his attention were 

 certain cpiantitative problems of cyanogenetic plants, the de- 

 termination of the amount of hydrocyanic acid capable of being 

 obtained from these plants by fermentation, and the isolation of 

 the glucoside of Ileterode^tdroii, one of our most fatal stock- 

 poisons. 



Mr. E. F. Kallmann, Linnean Macleay Fellow in Zoology, con- 

 ti'ibuted a paper descriptive of the genera Echinaxia and Rhah- 

 dvsignid, which was published in Part ii. of last year's Proceed- 

 ings. He also had under consideration a paper embodying 

 a reform in the classification of the Deamacidonidce, a rather 

 troublesome family to the systematist. At the end of the month, 



