Micro-organisms of Maple Sap 1 v . 



thus producing- a cloudy appearance. A characteristic surface 

 colony was formed. The medium remained unchanged until the 

 eighteenth to twentieth day when the first signs of liquefaction 

 were observed. The action was very feeble but persistent. Tubes 

 were completely liquefied in from 60 to 80 days. The cultures 

 30 days old exhibited infundibuliform or slightly napiform areas 

 of liquefaction extending from the surface down about 15 mm. 

 A heavy sediment deposited at the base of the liquefied portion 

 which was clear above and covered by a firm, dry layer which had 

 to be broken with a needle or by violent shaking in order to allow 

 the liquefied portion to run out when the tube was inverted. 



Gelatin colonics. — Growth upon gelatin plates developed 

 rapidly at 20 C, producing colonies at first round and finally 

 becoming deeply lobed under favorable moisture conditions. The 

 elevation of growth was convex. During the early stages the 

 colonies presented an entire edge becoming undulate the second 

 • lay, and thereafter gradually becoming deeply lobate. The in- 

 ternal structure was at first finely granular becoming deeply 

 reticulate or alveolar and developing a great variety of markings 

 during the transition. Colonies one week old were strikingly 

 characteristic, having a dark alveolar center surrounded by an 

 intermediate lighter zone bearing- finely reticulate markings, and 

 verging into the outer zone consisting of deeply cut compact 

 lobes composed of conglomerate aggregates, as if they had been 

 formed by repeated expanding, bursting and reforming of an 

 enveloping pseudomembrane. Liquefaction was not observed 

 upon gelatin plates. (Plate IX). 



Broth. — Cultures showed rapid growth and became semi- 

 opaque from clouding in 24 hours at 25 ° C. The clouding in- 

 creased for several days and was accompanied by the formation 

 of a flaky or somewhat membranous pellicle. The sediment at 

 first viscid became flaky in from 2 to 5 days. Cultures 6 to 8 

 weeks old were free from clouding with no pellicle but contained 

 a sediment which was viscid on agitation. The broth at this age 



