28 CIRCULAR NO. 110, BUREAU OF PLANT INDUSTRY. 



other by the alternate action of alkaline and acid reagents, though 

 both result in a yellow color under acid modification. 



This agrees so closely with the facts observed in the colored fibers 

 of the cotton cloth that it seems probable these colored fibers are 

 caused by growths of fungi, and probably of the species mentioned, 

 occurring upon cotton exposed to excessive dampness in the field or 

 picked in an unripe condition. The reason the fungus was not 

 discovered on the manufactured fibers is probably due to the mechani- 

 cal and chemical processes through which it passed. The samples of 

 cloth submitted had been mercerized. The external hyphae of the 

 fungus would probably be removed in the various processes of 

 ginning, spinning, • and subsequent treatment. The absence of 

 hyphae within the fibers may have been because of no penetration 

 having taken place in the specimens examined, or possibly because 

 of some obliterating effect of the process of mercerizing the cloth. 



The manufacturers are now preparing to adopt some means of 

 eliminating these undesirable samples of cotton from the raw material. 



U'ir. 110] 



