THE SLIME-FUNGI 



11 



(Gr. slcleros, hard). In this form a Myxomycete may 

 live for some years. When a sclerotium is damped, the 

 walls of the cysts are softened, and the organism resumes 

 its plasmodial form and activities. Fig. 4 shows a 

 group of the fruits, or sporangia, of the species Coma- 

 tricha obtusata, as well as an empty sporangium. The 

 spores which are formed in these vessels are quite dry 

 when they are exposed for distribution, and in a dry 



FIG. 5. SLIME -FUNGUS DIDYMIUM 

 DIFFORME. 



a, Spore; 6, swarm-cell emerging 

 from envelope ; c, swarm- cell 

 newly hatched ; d, swarm- cell 

 with flagellum ; e, swarm-cell 

 with bacteria in food vacuoles; 

 /, swarm-cell in amoeboid form, 

 x 720. 



FIG. 6. DIDYMIUM DIFFORME; 

 SWARM-CELLS ASSEMBLING AND 



COALESCING TO FORM A, PLAS- 

 MODIUM. 



m, An encysted swarm-cell; v., en- 

 cysted swarm-cell being digested 

 hi a vacuole ; s, empty spare 

 envelope. 



condition they retain their vitality for an indefinite 

 time. They can germinate only in moisture. The for- 

 mation and appearance of the swarm-spores is shown in 

 Fig. 5. The swarm- spores swim with what is described 

 as a " dancing movement "; they can digest solid food; 

 they increase by fission, and in a time of drought may 

 become encysted. As already stated, the swarm- 



