100 ACTINOMYCOSIS 



mycosis. Fig. 102 represents what is observed 

 when a granule from human actinomycotic pus is 

 crushed out in a little liq. potassse, washed in 

 ether and alcohol, and stained by Gram's method. 

 The nodule is seen to consist of a spherical mass of 

 interlaced mycelial filaments, consisting of a central 

 protoplasmic strand surrounded by a membrane. 

 This mycelium is the essential part of the micro- 

 organism, and is alone found in the cultures 

 (Fig. 103). The filaments grow in a radiate manner, 

 and are long, branched, often corkscrewed, and 

 frequently present a swelling at their extremities. 



Such forms can be seen in the photographs. The 

 mycelium stains well by Gram's method, shows 110- 

 trace of division, and its protoplasm is segregated 

 and granular. Very frequently small granules 

 (? spores) are found in the centres of the masses 

 which are derived by segmentation from the ends of 

 the filaments. 



Inoculated on the surface of blood serum or 

 glycerine-agar, growth takes place at 37 C. after 

 some days, and the inoculated granules gradually 

 increase in size, forming a dirty white, wrinkled, 

 raised growth. After some time, which is very vari- 

 able, the growth, especially where it is most elevated 

 and driest, becomes covered with a sulphur yellow 



