Ward . — Recent Researches on the Parasitism of Fungi . 39 
with well-staining nuclei and chlorophyll-corpuscles, and the cell-walls do 
not take up the fuchsin. 
Here, on the contrary, the cells in the immediate neighbourhood of the 
hyphae are often collapsed, their nuclei and chlorophyll-corpuscles dis- 
integrated and flowing together into shapeless masses, and deeply stained 
red, as are also the collapsed cell-walls. 
That this is a purely local phenomenon, confined to the immediate 
neighbourhood of the hyphae — which rarely send haustoria into the cells — 
is seen by the normal appearance and staining of cells further away. 
It is therefore impossible to accept the view that this collapse and 
abnormal behaviour of these nests of cells are due to the effects of 
preparation. 
The only conclusion we can come to is that the hyphae attack the cells 
too vigorously at the outset. Instead of capturing them, as it were, by 
putting in haustoria which delicately tap the cell-contents and make them 
serve as sources of food-supplies, the Fungus clumsily kills these cells, and 
is in consequence subjected to all the exigencies of starvation, or worse. 
Starvation Phenomena. 
Our reasons for this conclusion are not based only on the histological 
evidence afforded by these so-called ‘ immune ’ Wheats. 
We have induced starvation phenomena of substantially the same 
kind, even in susceptible Wheats, in which infection and the growth of the 
Fungus proceed normally under normal conditions ; and this in several ways. 
If infected leaves are cut off on the third day or so after infection, and 
floated on water, the Fungus may continue to grow, but it soon shows signs 
of starvation ; for although the leaves are exposed to light and go on form- 
ing carbohydrates, the mineral and soluble carbohydrate supplies soon run 
short, from being washed out, and other changes occur which bring the 
normal functions to a stop. 
The effects of mere mineral starvation have already been demonstrated 
by me ( 194 , 1902), but it is clear from our experiments that although they 
do not kill off the Fungus forthwith, they have their effect on the structure 
of the mycelium. 
Another way by means of which we have induced starvation pheno- 
mena is to keep the roots of the infected plants too hot or too cold for 
normal growth. This was effected by placing three pots of infected plants 
in reservoirs, plunged in water, in tin boxes. One, the control, was kept 
at the ordinary temperature ; the other was kept heated to temperatures 
about 3 °°-35° C. day and night by means of a lamp below ; and the third was 
kept chilled, by ice round the pot day and night, to near 5 0 C. and below. 
This treatment refers to the roots only : the foliage was freely exposed to 
