8 
INTRODUCTION. 
with this statement ; the cases of hybridism referred to by Mr. 
Massee in his Monogr-aph* appear to require confirmation. 
The food of plasmodia is often easy to determine. Those which 
live among dead leaves spread with veins which ai'e brown from 
the incorporation of decayed vegetable matter, and when the refuse 
is discharged they become white or yellow, according to the species, 
shortly before they form into sporangia. The plasmodium of 
Badhamia panicea thrives on the inner bark of felled elms, and 
is difS.cult to discern on the red-brown substratum owing to the 
broken fragments of bark with which it is densely charged ; it 
becomes pure white by the rejection of enclosed matter before 
fruiting. Occasionally the question of food is somewhat obscure ; 
for example, the plasmodium of Amauroclicete atra rises in cushions 
from half an inch to two inches in diameter, from the hard 
and apparently sound wood of 
Scotch firs ; that of Stemonitis 
sjjlendens may also be found 
emerging from the sawn sur- 
face of fir stumps, which show 
no sign of decay, and covering 
an area of six to seven square 
inches. Whatever solid matter 
these Plasmodia may have in- 
gested has been- parted with 
before leaving the wood, but 
it appears more probable that 
their food was absorbed in a 
state of solution. The yellow 
Plasmodium of Badhamia 
Pig. 5.— Badhamia dteicdlaris Berk. utricularis is the Only One 
Division of nuclei by kai70kinesis in the are acquainted with which 
streaming plasmodium. <? j t • e • i • 
Prom a preparation stained in safranin, and lOedS On ilVlUg tungl and IS 
mounted in Canada balsam. capable of being Cultivated 
Magnified 1200 times. , . . o 
Without limit on btereum 
'hirsutvm and allied species ; it can be observed under the micro- 
scope to dissolve fungus hyphte as the hyaline border of a wave 
of plasmodium advances over them.f The growth of this species 
is often very rapid ; a plasmodium measuring about a square inch 
in area on a large pileus of Auricularia mesenterica has been seen 
to increase during twenty hours so a,6 to cover more than six 
square inches ; the vigorous flow extended over the meshes between 
the veins and produced an unbroken surface. 
The multiplication of nuclei which takes place in such a 
growth as this, where we may assume, from numerous observa- 
tions, that they have increased at least sixfold, requires further 
investigation. That they sometimes divide by karyokinesis is 
* Mass., Mon., p. 15. 
t Lister, " Plasmodium of Badhamia," etc., Annals of Botany, vol. ii., 
p. 13. 
