THE MYCETOZOA 141 



magnification of 60 diams. showed typical streaming, but so 

 fragile was the plasmodium that on covering with a thin 

 cover-glass after adding a drop of water it broke up into 

 chalky subdivisions. 



The sclerotium. This resting state is one of the most 

 important phases of Mycetozoa. It develops only from 

 mature plasmodia, and 

 was discovered and 

 named by de Bary. The 

 beginning resembles the 

 first step towards spore- 

 formation : the plas- 

 modium concentrates at 



points and breaks up 



FIG. 39. SCLEROTIUM OF DIDYMIUM COM- 



into segments, Fig. 39, a ; PLANATUM. a, The whole sclerotium 



all food remains are re- about natural size ( {i had f rmed on a 



moss-stalk) ; 6, part of a section, from 



jected. Most, but not which the contents of two cysts have 



,, . fallen out ( x 250 diams.) ; c, return 



all, mycetozoan sclerotia of two elements to the amoeboid state. 



may be regarded as a x 25 diams - From Doflein > af ter de 



protective encystment, 



and compared to the formation of microcysts or to hypno- 

 cysts in protozoa. 



On being completely dried the sclerotium assumes a 

 horny brittle consistence. The minute subdivisions are 

 either round or oval, or, from mutual pressure, polyhedral 

 in form. In the latter case a section may have a curious 

 resemblance to the parenchyma of a plant, but on being 



