THE MULBERRY BLIGHT: CAUSE 



343 



in the absence of successful inoculations, if the author has tied 

 it to definite characters incompatible with parasitism, and the 

 organism in question is definitely parasitic. But sometimes, as in 

 this instance, contradictory statements are made. In such'^cases I 

 think we may retain the name and reject the contradictions pro- 



FiG. 264. — Diseased stems of mulberry showing extrusion of bacterial cirri 

 {Bacterium mori) through lenticels. Inoculated January 4, 1909. Photo- 

 graphed January IL 



vided there is a definite history of pathogenicity connected 

 with it. For these reasons I discard Bacterium oleae Archangeli 

 for which there is no history of pathogenicity and no proper 

 characterization (see No. XIII), and retain Bacterium viori 

 Boyer and Lambert where there is a correct account of the 



