1 6 Lister. — Notes on the Plasmodium of 
simultaneously influenced to withdraw to the food placed 
upon the glass plate below. 
Then again I have not been able to obtain any light on 
the impulse that occasions the change to sporangia. I have 
had a large supply of plasmodium spreading over a pile 
of Stereum under a bell-jar, and have removed portions into 
glass boxes and under glass shades, so that I have sometimes 
had seventeen separate colonies at one time, where the con- 
ditions of food and moisture have been apparently the same ; 
one after another of these colonies have undergone the 
change, while others continued to stream. Again, the whole 
of the main supply has suddenly formed into sporangia, 
some of them suspended in clusters by yellow threads or 
bands, and others formed into sessile plasmodiocarps upon 
the plate or pieces of Stereum ; the portions transferred to 
the smaller receptacles have meanwhile remained unaltered. 
On the other hand, so long as the plasmodium has been 
continuous, however extensive, the change to sporangia has 
taken place simultaneously throughout the whole 1 . There 
is no doubt that hot weather is unfavourable to the develop- 
ment of sporangia, but it is remarkable that for four 
months not a single colony went into its final stage ; 
though I should say that I lost a number from want of 
proper attention, they died and decomposed with a strong 
ammoniacal smell, having been poisoned by the products 
of the rapidly decaying Stereum. Many of the surviving 
colonies went into sporangia in the month of October ; one 
which changed on the 25th seems worthy of special mention. 
This was in part revived sclerotium which had dried in 
July. I wetted it on October 1, and it returned to active 
movement in the course of an hour or two ; to this I added 
about an equal quantity of plasmodium from the store under 
1 Since writing the above, a large growth of plasmodium has formed into spo- 
rangia under a bell-jar ; more than half changed on March 13, 1888, the rest on 
March 15. On March 11, when an appearance of sporangia occurred, I had added 
water, which checked the development. This plasmodium was a part of the 
continuous cultivation begun on Jan. 22, 1887. 
