EGG MEDIA 53 



[The quantities can, of course, be measured out with sterile pipettes into a 

 sterile vessel.] 

 3. Tube. Coagulate at 70-75 C. 



Glycerin-serum. 



An excellent culture medium for the tubercle bacillus is obtained by 

 mixing 6 to 8 per cent, of pure glycerin with serum. 



1. Aspirate 6 to 8 grams of pure glycerin, previously sterilized in the auto- 

 clave, into a Chamberland flask : 



2. Then 100 c.c. of sterile liquid serum into the same flask. (To facilitate 

 measurement the flask can be graduated beforehand.) 



3. Tube and .set at 75 C. This mixture requires a somewhat higher 

 temperature than ordinary serum. 



Serum-agar. Ascitic-agar. 



1. Dissolve 1*5 grams of agar in 100 c.c. of water. Filter. Tube (about 

 5 c.c. in each tube). Sterilize at 120 C. 



2. Cool to 40 C. To each tube add an equal volume of sterile serum or 

 sterile ascitic fluid. Mix gently by rotating the tubes in the hands. Cool 

 in the sloping position. 



Blood-agar. 1 



(Bezan$on and Griffon.) 



1. Take a number of tubes of glycerin-agar, melt in a water bath, and cool 

 to 40 C. 



2. Add to each tube a small quantity (about 1 c.c.) of blood from a rabbit's 

 artery (Chap. XII. ). Mix without shaking the tubes, and cool in a sloping 

 position. 



A solution of haemoglobin (p. 34) may be used instead of blood in this 

 case. 



Serum-agar. 



(Tochtermann.) 



1. Dissolve in 500 c.c. of boiling water 



Peptone (Chapoteaut, or Witte), 5 grams. 



Salt, - 2-50 



Glucose, 2-50 



Chopped and washed agar, - - - - - - 10 



2. Mix with the above solution 500 c.c. of sheep serum, and autoclave for 

 30 minutes at 115-120 C. 



3. Filter in the warm through moistened Chardin paper. Tube and 

 sterilize at 115 C. 



Egg. 

 Eggs can be used for the cultivation of micro-organisms in several ways. 



A. Take a fresh egg, shake it vigorously to mix the white and the yolk : 

 wash the shell in perchloride of mercury and dry with sterile filter paper. 

 Flame the narrow end until the shell blackens. Make a hole with a sterile 

 metal point. Pass a platinum wire or pipette charged with the material to 

 be sown through the hole, then close the latter with a little melted Golaz's 

 wax. It is well to coat the egg with a layer of collodion. 



B. Take a fresh egg, flame the pointed end, make a hole as described above : 

 aspirate the white into a sterile pipette. Tube in sterile tubes. Coagulate 



at 70 C. as in the case of serum. 





 1 See also under Pfeiffer's bacillus and Gonococcus. 



