APPENDIX 351 



Sodium carbonate, Na2COs . 60 gm. 



Calcium chloride, CaCk Trace 



Distilled water 1000 . c.c. 



Winogradski's medium for symbiotic nitrogen-fixation: 



nitrogen-free. 



Dibasic acid potassium phosphate, K2HP04. . 1.00 gm. 



Magnesium sulphate, MgS04 . 50 gm. 



Sodium chloride, NaCl 0.01 gm. 



Ferric sulphate,Fe 2 (864)3 - 0.01 gm. 



Manganese sulphate, MnS(>4 ,. . . 0.01 gm. 



Dextrose, CH 2 OH(CHOH) 4 CHO 20 . 00 gms. 



Distilled water 1000.00 c.c. 



Gelatin for cultivating phosphorescent halophilic or- 

 ganisms: Prepared as ordinary gelatin with the addition 

 of 3% salt. The reaction is made -20. 



Fermented cider for the cultivation of acetic bacteria: 

 Inoculate unfermented cider with Sacch. ellipsoideus and 

 allow to proceed until the evolution of gas ceases. Filter, 

 place in tubes and flasks as desired. Pasteurize. 



MEDIA FOR SOIL MICROBIOLOGY. 



Soil extract: 1. Boil 1 kg. of good rich garden soil 

 with 2 liters of tap water for two hours over the free flame. 



2. Pour off the turbid liquid, mix some talc- and filter 

 through a double filter paper. If the first filtrate is turbid 

 refilter through the same paper. 



3. Make up to 800 c.c. with tap water. 



4. Place in tubes or flasks as desired and autoclav. 

 Soil extract agar is prepared by adding 1.5% washed 



agar to the soil extract prepared as above. 



Soil may be plated either in soil extract agar (or other 

 special agar) or in ordinary agar, gelatin, etc. On account of 

 the diversity of the requirements of the various species of 



