J. Y. EvRK AMI E. S. Salmon 41tl» 



centration, however, its behaviour towards the mildew does appear 

 to approach that of the colourless amnionium sulphide. 



When colourless solutions of ammonium hydrosulphide and of 

 ammonium sulphide are allowed to stand exposed to atmospheric 

 oxyi,fen, they develop a yellow colour due to the formation of poly- 

 sulphides in the solutions and it is observed that this change, although 

 not altering appreciably the concentration of sulphide-sulphur, is 

 attended by an increased fungicidal action of these solutions. 



From these results it seems clear that the form in which sulphur 

 functions as a fungicide in these solutions is that known as the poly- 

 sulphide form. 



VII. LlMP>SuLPHUR. 



Hops. 1914. 



Exper. 1. Solution of l-OO'j sp. gr. (containing 0-7% S.S.) and 

 0-125 % saponin. 



1st day. Most of the patches well covered over by the deposit; a few patches 



showing the conidiophores uncovered or breaking through. 



3rd day. As above. 



5tli day. Conidiophores still visible on some patches, but not apparently 

 increasing. 



Stk day. Many of the patches dead ; the few alive very weak. 



12//( day. A very few conidiophores visilile on a few patches. 



Exper. 2. Solution of 1-005 sp. (jr. {containing 0-7 % S.S.) and 

 0-25 % saponin. 



Isl day. Many of the patches showing the conidiophores uncovered by the 

 deposit. 



3)y/ day. Nearly all the patches showing the conidiophores matted together; 

 on a few patches the conidiophores were erect and apparently vigorous. 



dth day. As above. 



8^/i day. Nearly all the patches apparently dying or dead; in a very few cases 

 a minute group of conidiophores was visible. 



\2/li day. Some patches still showing a few conidiophores. 



Exper. 3. Solution of l-OOo sp. gr. {containing 0-7% S.S.) and 

 0-25 % saponin. 



Isl day. The patches all well covered over, some showing the conidiophores 

 still erect, some with conidiophores collapsed. 



4lli day. No new conidiophores formed; all the patches still well covered. 

 ()//( day. All the patches remaining dormant, 

 Ulli day. All the patches dead. 



.33—2 



