THE MULBERRY BLIGHT: CAUSE 



347 



the American species, believing the French organism could not 

 be different from our own. In this belief I was entirely right, 

 as subsequent observations and experiments have proved (1913). 

 With these introductory comments we may proceed to a 

 statement of the characters of Bacteriu7n jnori B. and L., drawn 

 entirely from studies made in my laboratory, using cultures de- 

 rived both from American and French sources. 



Fig. 268. — Cross-section of young stem of mulberry showing the inner cortex 

 honeycombed by cavities due to Bacterium mori. A natural infection from 

 Arkansas. 1908. Medium magnification. 



Bacterium mori B. and L. emend. EFS., is a white, non-viscid 

 or slightly viscid (potato), slow-growing, non-sporiferous, non- 

 capsulate, actively motile (1-7 polar flagella, usually 1-4), 

 Gram-negative, non-gas-forming, strongly aerobic, non-lique- 

 fying (gelatin and L6 filer's solidified blood serum), non-nitrate- 

 reducing, acid-sensitive (Cohn's solution), sunlight-sensitive, 



