1922] 



YOUNG — THE TOXIC PROPERTY OF SULPHUR 



419 



TABLE I 



Organism 



Botrytis cinerea. 



Colletotrichum 

 Gossypii 



PERCENTAGE OF GERMINATION* 



Form of Sulphur 



Hydrogen-ion concentration (P H ) 



Without sulphur 



Flowers of sulphur 



Ground flowers of sulphur 



Hydrophilic colloidal 



sulphur 



Hydrophobic colloidal 



sulphur 



Precipitated lime sulphur 



Without sulphur 



Flowers of sulphur 



Ground flowers of sulphur 

 Hydrophilic colloidal 



sulphur 



Hydrophobic colloidal 



sulphur 



Precipitated lime sulphur 



Sclerotinia 

 cinerea 



Gloeosporium 

 venetum 



Macrosporium 

 sarcinaeforme 



1.6 



4 

 4 

 4 



6 



4 



Without sulphur 



Flowers of sulphur.... 



Hydrophilic colloidal 



sulphur 



Without sulphur 



Flowers of sulphur 



Ground flowers of sulphur 

 Hydrophilic colloidal 

 sulphur 



Without sulphur 



Flowers of sulphur 



Ground fiowers of sulphur 

 Hydrophilic colloidal 

 sulphur 



Phomopsis Sojae 



Without sulphur 



Flowers of sulphur 





 

 









 





 









 

 









 















2.4 



76 

 74 

 66 



60 



74 

 60 



3.2 









 









 



48 

 







4 

 3 

 3 



4 





4 

 4 

 4 









 



94 

 91 



78 



45 



81 

 52 



24 

 21 

 23 



1 



28 

 12 



72 

 







36 

 34 

 21 



20 



4.2 



90 

 91 



49 



10 



51 



20 



60 

 61 

 45 



19 



1 

 



35 

 28 

 25 



1 



31 

 13 



94 











5.4 



86 

 84 

 68 



8 



64 

 16 



57 

 47 



28 



5.8 



76 

 68 



65 

 60 

 46 



5 



30 

 11 



82 

 







85 

 83 

 45 



3 





42 

 



75 

 68 

 40 



1 



86 

 76 

 56 



2 



31 







64 

 61 



6.4 



56 

 51 

 52 



58 



74 

 17 



80 

 







65 

 65 



83 

 



48 

 46 

 35 



10 



52 

 26 



6.8 



34 

 33 



76 

 







60 

 58 

 55 



34 



68 

 68 

 61 



41 







22 



40 

 40 



29 

 



7.4 



24 

 23 

 16 



23 



21 



18 



36 



38 

 30 



15 



34 



28 







60 

 59 



3 

 







8.4 





 

 







63 

 



18 

 21 

 15 



14 



52 

 55 



48 



30 



37 

 



18 

 21 



20 





 







2 

 4 

 3 



6 



40 

 41 

 40 



38 



26 

 



Average of 6-12 replications conducted at 3 different times. 



EXPERIMENT 5. THE TOXICITY OF THE VOLATILE 



PRODUCTS OF SULPHUR 



The results of the foregoing experiments indicate that sulphur 

 is most toxic when it is in a finely divided state, this toxicity in- 

 creasing in proportion to the fineness of the particle, hydrophilic 

 colloidal sulphur exhibiting the highest degree of toxicity. The 

 prevailing supposition that sulphur is only toxic when in a vol- 

 atile state might be justified by the assumption that finely di- 



