88 MICROBIOLOGY 



Uschinsky's Proteid-Free Medium. 1 To one liter of dis- 

 tilled water add: 



Asparagin 3.4 grams 



Ammonium lactate 10.0 " 



Sodium chloride 5.0 " 



Magnesium sulphate 0.2 " 



Calcium chloride 0.1 " 



Potassium phosphate 1.0 " 



When these substances are thoroughly dissolved, add 40 cc. 

 of glycerin. Tube and sterilize. 

 Conn's Solution. 



1. Weigh out and mix 



Acid potassium phosphate 5.00 grams 



Tribasic calcium phosphate 0.50 gram 



Magnesium phosphate 5.00 grams 



Ammonium tartrate 10.00 grams 



and dissolve in distilled water 1000 cc. 



2. Tube or flask and sterilize. 



Synthetic media. In the cultivation of bacteria it has 

 been shown that certain of them will grow in media com- 

 posed largely of various inorganic compounds. Many such 

 synthetic media have been proposed especially for the culti- 

 vation of bacteria where a chemical analysis has to be made 

 either of the organisms themselves or to determine the effect 

 of their multiplication on the medium. A large amount of 

 work has been done on this subject by Gorham and his stu- 

 dents. The formulae for a few of the more simple nutrient 

 solutions are appended. The one of Uschinsky has been used 

 somewhat extensively. 



Uschinsky's solution. Mix the following substances, dis- 

 tribute in tubes. Sterilize. 



1 Ushinsky. Cent. f. Bakt., Bd. XIV (1893) p. 316. 



