Micro-organisms of Maple Sap 4<l» 



consistency and was found only a few times during the progress 



of the studies. 



Such a specimen of sap was first received in the laboratory 

 during the sugar season of [908. It possessed a decidedly 



stringy character, being so ropy that after turning a little of ii 

 from the Mask in which it was received the material continued to 

 siphon from the container, even when its mouth was turned up 

 so as to he somewhat above the level of the sap within. The 

 material was uniform in consistency, milky in color, and possessed 

 a pronounced yeasty odor. Examination under the microscope 

 revealed enormous numbers of actively motile bacteria apparently 

 in almost pure culture. When plates were poured almost all the 

 colonies developing were of one type. Cultures obtained from these 

 were found capable of reproducing the characters of the original 

 material when introduced into fresh maple sap. As explained 

 under the head "Cultural Characters," page 403, the stringy 

 property developed to a pronounced degree only in unsterilized 

 sap, but since it always appeared after inoculation with this or- 

 ganism, and only when this organism was employed, and since 

 the bacillus was always recovered from the inoculated material in 

 practically pure cultures, there can be no doubt of its causal rela 

 tion to the condition of the sap. 



The organism has a very detrimental influence upon the 

 quality of sirup. While the color is not always seriously impaired 

 the sirup is made more or less cloudy, a very unnatural and 1111 

 pleasant flavor is developed, and the amount of invert sugar i^ 

 increased by the action of the organism. 



FORM 

 The organism is a bacillus with rounded ends, occurring 

 singly, in pairs, or often in filaments in young agar or nutrient 

 broth cultures at 20-25 C. Short chains 1 5 to 7 segments) often 

 occur in cultures 24 hours old and chains of 20 or more segments 

 are not infrequent. The tendency to chain formation is less pro 

 nounced in the older cultures and persists longer upon solid media 

 than in liquid cultures. 



