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NOTE. 
ON THE PARASITIC HABITS OF THE PLASMODIUM 
OF PHYSARUM VIRIDE VAR. RIGIDUM LISTER. 
The following notes refer to the habitat of the plasmodium 
of Physarum viride var. rigidum as seen in tropical Malaya. 
Here this is one of the commonest and most widely distributed 
species, occurring especially on decaying logs of Hevea brasili- 
ensis. My attention was first drawn to its possible parasitic 
nature by repeatedly finding the sporangia on or near the white 
fan-shaped pilei of Schizophyllum commune, the commonest of 
the Agaricineae found on dead Hevea; moreover the pilei on 
which sporangia occurred invariably presented a dried up, 
shrivelled, dead appearance. When the sporangia occurred on 
the bark of Hevea there were almost always masses of dead 
shrivelled Schizophyllum near by. That this appearance was 
not due to weather conditions was proved by the presence of 
other fresh growths of Schizophyllum on the same log; traces 
of the veins of the plasmodium could always be found on pilei 
bearing sporangia of the Physarum as well as on others free 
from sporangia in the immediate neighbourhood. 
These field observations suggested an investigation into the 
habits of this plasmodium, and the following experiments were 
carried out. 
Spores from freshly collected sporangia of the Physarum were 
sprinkled on damp fresh pilei of Schizophyllum gathered from 
a log showing no trace of Mycetozoa. In 48 hours yellow 
plasmodium was seen on the inoculated material kept in a damp 
chamber; most of the Schizophyllum was then still alive, as 
evidenced by the formation of new outgrowths at the bases of 
the stalks, but the parts of the upper surface of the pileus over 
which the plasmodium spread had turned a dirty brown. This 
change in colour and general appearance became more and more 
accentuated each succeeding 24 hours and by the sixth day all 
the Schizophyllum had been killed, the whole being then a 
dirty wet brown flaccid mass; from this the plasmodium was 
retiring and had begun to spread over the sides of the glass dish. 
Fresh pilei were placed in contact with the plasmodium, which 
in another 24 hours was spreading over the new food material. 
The plasmodium began to gather together into small masses 
preparatory to fruiting which took place the following day. 
The sporangia were at first yellow and remained so for some 
time. The final colour change occurred quickly, and almost 
simultaneously over the hundreds of sporangia, from a bright 
yellow to bronze brown. The final metallic bronzed appearance 
