THE ASEPTIC CULTIVATION OF MYCETOZOA. 61 



and again moistened they gave origin to active zoospores. He 

 thus reached the conclusion that the plasraodia did not digest 

 the microcysts. 



It is well to consider the condition under which he placed 

 the Plasmodia. He removed them from the fluid to which they 

 were accustomed, washed them in fresh water, and placed the 

 microcysts, spores, &c., on or near the plasmodia. In some 

 instances he washed them several times. To the writer this 

 seems harsh treatment. It cannot be wondered at that they 

 were not in a condition to digest foreign substances, and that 

 under normal conditions he got peculiar results. 



The writer has observed living plasmodia which had taken 

 in microcysts and rounded off zoospores which had not yet 

 formed a cyst wall. In these instances the zoospores were 

 lying in vacuoles. Plasmodia placed on slides under a 

 cover-glass (with active and encysted zoospores in the same fluid 

 in which they grew) and allowed to spread out were killed with 

 picric and acetic acid, and stained with picro-carmine. One 

 finds in such specimens microcysts and rounded-off zoospores 

 lying in vacuoles. They are in various stages of degenera- 

 tion, and stained with varying degrees of intensity. From a 

 study of the specimens the writer does not see how one can 

 reach any other conclusion but that the microcysts and 

 zoospores are digested. If one examines a culture after 

 having developed sporangia, there are a smaller number of 

 microcysts present than there was some time previously. 



If one places a few drops of a culture containing zoospores 

 of Stemonitis on a slide under a cover-glass, placing it in a 

 moist chamber for some hours, on examination he will find 

 many of the zoospores creeping around on the slide, feeding 

 on the bacteria. If, now, a point is examined at one side of 

 the cover-glass, and a drop of sterilised water be added to the 

 culture at the opposite side of the cover-glass, it will be 

 observed that the zoospores instantly draw themselves 

 together, many of the vacuoles will disappear, and the bacteria 

 or undigested granules which were in the vacuoles will appear 

 as granular particles enclosed in the protoplasm. It will be 



