CULTIVATION OF ACTINOMYCES. 



269 





takes place at the ordinary room temperature, but very slowly, 

 the temperature of the body being much more suitable. 



On cigar or glycerine-agar at 37 C., growth is generally 

 visible on the third or fourth day in the form of little 

 transparent drops which gradually enlarge and form rounded 

 projections of a reddish-yellow tint and somewhat trans- 

 parent appearance, like drops of amber. The growths 

 tend to remain separate, and even when they become 

 confluent, the nodular character is maintained. They have 

 a tough consistence, being with difficulty broken up, and 

 adhere firmly to the surface of the agar. Older growths 

 often show on the surface a sort of corrugated aspect, 

 and may sometimes present the appearance of having 

 been dusted with a brownish-yellow powder (Fig. 68). 

 The organism grows well in the anaerobic condition on 

 agar, and for this purpose unopened eggs also, either in 

 the fresh or boiled 

 condition, have been 

 used, inoculation 

 being effected by 

 drilling in the shell 

 a small hole which 

 is afterwards closed. 

 The growth on 

 potatoes is somewhat 

 similar to that on 

 agar. 



On gelatine the 

 same tendency to 

 grow in little spheri- 

 cal masses is seen, 



and the medium FIG. 69. Actinomyces, from a culture on 

 becomes very slowly glycerine-agar ; showing the branching of the 

 i> / j TT 7-1 .1 filaments. 



liquefied. When this Stained with fuchsin x I000 

 occurs the liquefied 



portion has a brownish and somewhat syrupy consistence, 

 and the growths may be seen at the bottom, as little 

 balls, from the surface of which filaments radiate. 



