[hareison & barlow] slime-producing ORGANISM 121 



The reaction in sucrose agar culture — 13° was acid in the agar of 

 the slope, that is in the vicinity of growth, but was alkaline in the agar 

 in the deepest part of the same tube. 



Alkaline sucrose agars were inoculated and the sucrose was inverted 

 but the medium beneath the active growth was found to liave become 

 acid by the time the inversion was observed and it is probable that the 

 invertase acted onl}^ in an acid medium. Uninoculated controls showed 

 no inversion and remained alkaline. 



The Effect of Desiccation. — Two agar cultures grown at 18° to 

 22° C. were used. One was two days old, the other 45 days old. A 

 covergiass was held in flamed forceps and flamed. When it was cool 

 a 2 m.m. loopful of the slimy culture was spread on it and it was then 

 put in a sterile Petri dish. In this way a number of coverglasses were 

 prepared from each cultures and the two dishes were kept at 18° 

 to 22 °C. 



At intervals of a few days, one of the coverglasses from each lot 

 was dropped into a tube of Dunham's solution. If, on incubation, the 

 medium became turbid and slimy with a ropy sediment and a green- 

 blue color, the desiccated culture was said to be alive. If the medium 

 remained clear, the culture was said to be dead. The trials were too 

 few and far between and the limits were not accurately determined. 



The culture which was two days old was alive after desiccation for 

 7, 13, 36 and 38 days, but dead on one covergiass after 32 days. 



The culture which was 45 days old was alive after 4, 7 and 13 days 

 and dead after 32 and 38 days of desiccation. 



Growth at Loiv Temperatures. — Cultures were made on lactose 

 agar and in lactose and sucrose bouillon and placed in our cold-storage 

 building. 



The highest observed temperature was 1.6° C. and the lowest — 1° 0. 

 The temperature was about 1.5° C. most of the time. In 24 hours 

 there was slight growth, in 2 days there was little gro-^^h on agar and on 

 agar containing 1^ and 20^ sucrose, no growth on agar with 1/10^, 

 5^ or 25^ sucrose. After 6 days there was growth on all except the 

 25;i^ lactose agar, which at the low temperature was more than saturated 

 with lactose so that crystals formed. In 13 days the growth had 

 increased, but was thin and retarded compared ^vith growth in the same 

 media at 18° to 22° C. The growth was iridescent by electric light 

 but not in daylight. No pigment appeared in 6 days. In 13 days 

 10^ lactose agar was light blue almost throughout, 1^ and 5;^ were light 

 blue in the upper half of the inclined agar, 1/10^ showed a greenish 

 tint and 20^, 25^ and agar without lactose showed no pigment. After 



