76 BACTERIOLOGY. 



bouillon containing 1 per cent, of grape-sugar, and three 

 parts of blood-serum. This mixture is placed in test- 

 tubes, sterilized, and solidified in exactly the way given 

 for blood serum. 



Guarniari's agar-gelatin : 



Meat-infusion . 950 c.c. 



Sodium chloride . . 5 grammes. 



Peptone . . . 25-30 " 



Gelatin . 40-60 " 



Agar-agar . . 3-4 " 



Water ^ 50 c.c. 



The point in the preparation of this medium is its 

 reaction, which should be exactly neutral. 



The list of special media is too great to be given in a 

 work of this size. Their description must be seen in the 

 original. Those which have been given above will 

 suffice for obtaining a clear understanding of the prin- 

 ciples of the work. 



Note. — The term " meat-infusion " always implies a 

 watery extract of meat made by mixing 500 grammes of 

 finely-chopped lean meat and 1 litre of water together, 

 and allowing them to stand in a cool place for twenty- 

 four hours. At the end of this time the fluid portion is 

 strained off through a coarse towel. This represents the 

 infusion. 



