146 PROTESTS AND DISEASE 



appear to become a kind of sclerotium ; it was from one 

 such that the large double cells Fig. 18, Part IV, 

 developed. 



In Fig. 26, Part IV, is shown a section of an early 

 sporangium ; in a plasmodial lobe are two large chromidial 

 bodies, and in a space between the lobes is what I called a 

 spore, but the different nature of which has been explained 

 by a later experience. In 1920 on teasing in water one of a 

 group of ordinary-looking sporangia of Didymium difforme 

 I found instead of the usual mass of dark brown spores 

 there were only one or two such in the field and no capil- 

 litium fibres ; but many concentrically striated bodies. 

 The latter in a slide-and-cover preparation first swelled, 

 and on the 4th day, expanded into streaks with a red core ; 

 the streaks changed into ordinary capillitium fibres. The 

 red colour was no doubt a prismatic effect ; the coloured 

 parts looked black when out of focus. 



The chromidial processes appear to be used largely for 

 the production of capillitium elements ; I would designate 

 such chromidial matter skeletoplasm. I was unable to 

 find another sporange in which the concentric bodies were 

 present, but I found later that, if slides washed in water 

 and then wiped dry after they have been in 5 % solution 

 of lysol are used, sporangia of various Mycetozoa give when 

 teased in water a simulation of the red streaks with some 

 imitation of capillitium-formation. Lysol is made by boiling 

 either linseed oil or resin with tar oil, alcohol, and potash. 



