Micro-organisms of Maple Sap 518 



to flasks containing 49. 99, 149 and [99 cc. respectively of dis- 

 tilled water. From each of these flasks portions of 1 cc. were with- 

 drawn with sterile pipettes and placed in test tubes containing 

 10 cc. of broth, thus making dilutions of 1-550, 1-1100, 1-1650 

 and 1-2200 respectively. Eight tubes of each dilution were pre- 

 pared, 5 tubes were inoculated with a 2 mm. loop of a 24 hour old 

 broth culture, and 3 were retained as controls. Incubation was at 

 25 C. No growth had developed in any of the tubes at the end 

 of 2 days. On the fourth day growth was observed in one of the 

 five tubes containing- 1 part of formalin to 2200 of water. Thir- 

 teen days after inoculation transfers were made into sterile broth. 

 The transfers from the tube showing growth developed a charac- 

 teristic appearance but those from the other tubes remained un- 

 changed. In the second series 1 cc. of 40/Y formaldehyde was 

 added to flasks containing' 199, 249 and 299 cc. respectively of 

 distilled water. One cc. portions were transferred with sterile 

 pipettes to tubes containing- 10 cc. Of broth, thus making dilutions 

 of approximately 1 part of formalin in 2200, 2750, and 3300 parts 

 respectively. As in the previous instance 5 tubes were inoculated 

 and 3 retained as checks. \Vithin24 hours growth appeared in 3 

 of the 5 tubes containing- 1 part of formalin to 3300. The second 

 day growth was evident in all of the tubes containing 1 part of 

 formalin to 3300 and in one of the tubes containing 1 part to 

 2750. The cultures f> days old showed growth in all tubes of the 

 weakest dilution, in 3 of the 5 tubes containing t part formalin to 

 2750 of the medium, and a very slight growth in one of the tubes 

 containing- 1 to 2200. ( )n the eleventh day the tubes had all 

 cleared except one containing formalin in the proportion of 1 to 

 3300. This tube showed strong clouding. 



Phenol. — The phenol employed in this work was Merck's 

 phenol, U. S. P. VII. This was melted by placing the container 

 in warm water. To a portion was added 1 1 ' < of water h\ 

 weight, thus obtaining a solution which remained liquid at ordin- 

 ary temperatures. One cc. of this liquid phenol was added to 

 9, 49, 99, 149, and 199 cc. respectively of distilled water. One 



