50 



in alkaline beef broth. Ps. stevmrti grew in this broth without 

 retardation. Three saproph^^tic bacteria, obtained by Mr. A. F. 

 Woods from the surface of carnation leaves, also clouded this broth 

 in 2 to 7 daj^s, viz, a pink buff germ, a lemon mellow germ, and an 

 orange colored germ, the latter probably identical with Bactet^lum, 

 dianth i A-vthnv and Bolley. (See also Growth in fluid media.) 



Cabbage Juice. 



This fluid was prepared by grinding green cabbage leaves and 

 extracting the juice under pressure. No water was added. The leaves 

 were from old, slow-growing, hothouse plants. This juice was 

 divided into two portions, one of which was sterilized bv forcing it 

 through a Chamberland filter, and the other by steaming for a few 

 minutes on 3 consecutive da3\s. There was no difi'erence in the acidity, 

 each titrating +-^0 with caustic soda and phenolphthalein. The l)oiled 

 juice smelled strongly of cabbage. Each stock Avas inoculated in the 

 same way, i. e., with a small mass of bright yellow slime from a 

 starch-jelly culture 28 days old. The tubes were well plugged and 

 set in a dark place exposed to room temperatures of 22° to 33° C. 

 (mostly 25° to 29°). 



Besult. — One tube of the filtered juice was under observ^ation 44 

 da^^s, but no growth appeared. Two tubes of the boiled juice were 

 under observation, respectively, 29 and 44 da^^s, but there was no 

 growth. Five tubes of slant agar were inoculated at the same time 

 from the same culture, and all took readih\ Knowing that bac- 

 teria will tolerate more acid in a solid than in a fluid medium, 150 

 mgs. of Lautenschlager's neutral agar flour was added to one of 

 the tubes on the twenty-ninth da3\ This was then steam sterilized, 

 slanted, and the surface carefuil}' streaked with at least a cubic milli- 

 meter of bright yellow slime from an agar culture 4 davs old. This 

 slant culture Avas under observation, in conditions favorable to growth, 

 for 45 days, but no growth ensued, except on the wall of the tube above 

 the slant in a place which was accidentally touched b}^ the loop and 

 where a little moisture condensed. 



Ps. 2)^ictseoli and Ps. campestris also refused to grow in this acid 

 cabbage juice; but when the fluid was solidified by adding 150 mgs. of 

 the agar flour the latter made a verj' copious and prolonged growth — 

 i. e., much better than on ordinar}^ ^gar, although it was started upon 

 it Avith great difficulty (3 copious inoculations). On the contrary. 

 Bacillus amylovorus and 7^'. steirartl grcAV in the boiled juice Avithout 

 retardation. The latter, inoculated from a solid culture, clouded the 

 fluid (2 tubes) in less than 48 hours and made a very prolonged and 

 copious growth. B. amylovorus grew nearly as Avell. 



