151 



Behavior in Dun- 

 ham's solution 

 with alcoholic so- 

 lution of rosolic 

 acid and a small 

 amount of HCl. 



Behavior in chloro- 

 formed beef broth. 



l1. Between the 6th and 9th day the pale orange yellow fluid 

 changes to a geranium red, which gradually deepens to 

 poppy red (37th to 56th day). Ps. campestris. 



2. The color changes follow the same general course as in the 



preceding, but much more slowly; i. e., no distinct change 

 of color until after the 16th day and not so deep on the 

 56th day. Ps. steivarti. 



3. The yellow color of the fluid gradually bleached and practi- 



calh'all gone at the end of the second week; no reddening 

 of the fluid. Ps. hyacinthi. 



1. No growth. Ps. campestris. (Only one experiment.) 



2. Slow, long-continued growth, but with much difficulty iu 



ge':ting started. Ps. hyacinthi, Ps. phaseoli. 



3. Good growth, with little difficulty in getting started. Ps. 



stewarti. 



Behavior in distilled 

 water containing 

 4 per cent maltose 

 and 4 per cent 

 Witte's peptonum 

 siccum. 



1. Fluid in old cultures (40 to 60 days) distinctly browned. 



cariipcstris. 



2. Fluid not browned. Ps. phaseoli. 



P.S. 



Growth on 10 c. c. 

 slant nutrient agar 

 containing 3 grams 

 of cane sugar. 



Behavior on 10 c. c. 

 slant nutrient agar 

 containing 1 gram 

 of grape sugar. 



Behavior on 10 c. c. 

 of slant nutrient 

 starch jelly con-< 

 taining 500 mgs. of 

 glycerin. 



Behavior on slant nu- 



1. No distinct retardation, surface smooth, slime cojiious, and 

 generally wet enough to flow readily. Ps. campestris, Ps. 

 phaseoli. 

 Marked retardation of growth, surface roughened, reticulated 

 or areolated, slime dry so that it does not flow. Ps. Iiya- 

 cintJii. 



1. Growth copious, stimulated from the start. Ps. campestris, 



Ps. phaseoli, Ps. stewarti. 



2. Growth retarded for a week or more, ])ut finally better than 



in the check tubes. Ps. hyacimthi. 



1. Growth, after 24 days, copious, sirupy, bright yellow. Ps. 



campestris. 



2. Growth, after 24 days, much less than in the preceding or 



than in the check tubes, and with no distinct yellow 

 color. Ps. phaseoli. 



trient starch jelly 

 made with modi- 

 fied Uchinsky's 

 solution (see p. 63). 



Behavior in I^chin- 

 skv's solution. 



Thermal death point 

 (10 min. expos- 

 ure iu beef bouil- 

 lon) . 



1. Growth good, slime yellow, marked diastasic action. Ps. 



campestris. 



2. Growth much less abundant than in the preceding and slime 



very pale, marked diastasic action. Ps. phaseoli. 



3. Growth feeble, no diastasic action. Ps. hyacinthi. 



1 . No growth or growth long delayed and feeble, with appear- 



ance in the fluid of small, whitish, loose, wooly flocks. 

 Ps. Jiyacinlhi. 



2. Growth retarded and feeble, zoogloefe compact, roundish. 



Ps. campestris. 



3. As in 2, V)ut a yellower and rather ])etter growth. Ps. 



phaseoli. 



4. An al)undant and long-continued growth — a very suitable 



culture medium. Px. steu-arti. 

 { 1 ) 53° C. Ps. stacarti. 



(2) 51.5° C. 



(3) 49.5° C. 



(4) 47.5° C. 



Ps. campestris. 

 Ps. phaseoli. 

 Ps. }u/aci)ithi. 



