LABORATORY AND TEACHING METHODS 593 



Ptazmcwski's Culture Fluid. 



Dipotassium phosphate 5 . o gr. 



Magnesium sulphate 5.0 



Ammonium carbonate 5.0 



Calcium chloride 0.5 



Distilled water 1000. o c.c. 



Dissolve cold. Any desired sugar may be added as carbon food. 

 Adolf Mayer's Culture Fluid (Unters ii-d. ale. Gahr., 1870). 



Magnesium sulphate 10. o gr. 



Ammonium nitrate 15.0 



Tri-basic calcium phosphate o. i 



Potassium phosphate 10. o 



Distilled water , 1000. o c.c. 



Dissolve cold and add sugar. Add NaCl (3 per cent.), if it is to be used for 

 luminous bacteria, and an excess of pure carbonate of hme, if acid-forming bacteria 

 are to be grown. 



Uschinsky's Sclution. 



Distilled water 1000 c.c. 



Glycerin 30-40 gr . 



Sodium chloride 5-7 



Calcium chloride o. i 



Magnesium sulphate 0.3 to 0.4 



Dipotassium phosphate 2 . o to 2 . 5 



Ammonium lactate 6-7 



Sodium asparaginate 3-4 



Modified Uschinsky's Sclution. — The modified Uschinsky's recommended by 

 Smith for use with starch jelly is made as follows: 



Distilled water 1000.00 c.c. 



Ammonium lactate 5 . 00 gr. 



Sodium asparaginate , 2 . 50 



Sodium sulphate 2.50 



Sodium chloride 2 . 50 



Dipotassium phosphate 2 . 50 



Calcium chloride o.oi 



Magnesium sulphate o.oi 



Fraenkel and Voges' Solution. 



Water 1000 c.c. 



Sodium chloride 5 gr- 



Dipotassium phosphate 3 



Ammonium lactate 6 



Sodium asparaginate 4 



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