J. V. Eyre axd E. S. Salmon 497 



VI. Ammonium Sulphide (Colourle.ss). 



AiinnoniuDi Hijdrosulphide. 



Exper. 1. Sohdiiiii (pule ijellow) containing 1-65 % S.S. uiul 1 % 

 soft soap. 



Ist day. The patches checked, with the myceUuiii apparently more or less 

 collapsed in places; some short conidiopliores visible. 



'ird day. The mildew apparently regrowing anil forming fresh conidiopliores. 



llh day. The majority of the patches on each leaf now with vigorous ttifts 

 of ahuost or quite powdery conidiophores. 



Exper. 2. Solution [rolourless) conlaiitinu 3-;36 % S.S. and 1% soft 

 soap. 



1st day. Patches slightly checked; hundreds of young conidiophores visible. 



ith day. The majority of the patches, although still somewhat checked, showing 

 groups of numerous, long conidiophores ; the mycehum not collapsed and Hocculent. 

 On two out of the four leaves injury apparent in the form of a small brown "scorched" 

 spot. 



oth day. Some of the patches subpowderv. 



1th day. The majority of the patches now "powdery." 



Exper. 3. Solution {i/ellow) containimj .3-31 % S.S. and 1 % soft soap. 

 (This was the same solution as used above m Exj^er. 2, 

 after one day's exposure to air in a half-filled 

 stoppered bottle.) 

 2nd day. ilildew greatly checked. 



Zrd day. All the patches greatly checked, mostly sterile, but weak conidiophores 

 visible here and there in several places on each leaf. 

 Uli day. Mildew white, but dormant and sterile. 



&h day. Patches mostly sterile, but some bearing a few weak scattered conidio- 

 phores. 



10th day. Most of the patches on two leaves now with abundant conidiophores 

 and almost powdery; on the third leaf many patches dead, but some patches 

 bearing a few conidiophores. 



Ammonium Sulphide [colourless). 



Exper. 1. Solution {colourless) containing 1-68% S.S. and 1% soft 

 soup. 



Isl day. Patches shghtly checked ; hundreds of yoiuig conidiophores visible. 

 Slight traces of injury to some leaves. 



4fh day. Mildew still checked, with the mycelial hyphae apparently more or 

 less collapsed in places ; numerous groups of tall conidiophores produced freely 

 on some of the patches. Distinct injury in the form of brown (dead) patches of 

 leaf-cells on two leaves; similar injury, but more sliglit, on the four other leaves. 



Journ. of Agrio. Sci. vn 33 



