LABORATORY AND TEACHING METHODS 593 



Praznwwski's Culture Fluid. 



Dipotassium phosphate s.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 u-d. ale. Gahr., 1870). 



Magnesium sulphate 10. o gr. 



Ammonium nitrate iS-o 



Tii-basic calcium phosphate o. i 



Potassium phosphate 10.0 



Distilled water 1000 .0 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 lime, if acid-forming bacteria 

 are to be grown. 



Uschinsky's Solution. 



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-°° gr. 



Sodium asparaginate 2.50 



Sodium sulphate 2 . 50 



Sodium chloride 2.3° 



Dipotassium phosphate 2 . 30 



Calcium chloride o.oi 



Magnesium sulphate o.oi 



Fraenkel and Voges' Solution. 



Water 1000 c.c. 



Sodium chloride S gr. 



Dipotassium phosphate 2 



Ammonium lactate 6 



Sodium asparaginate 4 



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