Lutman—Life History and Cytology of the Smuts. 1217 
(34) stated it, sending out short projections which become 
closely appressed to the cell wall to form a sort of appressorium 
(Figs. 63, 70, 71) such as occurs in the mildews except that in 
this case it is much larger and better developed. The host cell 
wall under this appressorium ultimately becomes dissolved away 
and a hvpha is pushed down from its middle into the cell. In 
the meantime, however, the host cell is not entirely passive; as 
a response to the irritation of the appressorium it has thickened 
its wall under the spot where the stimulus occurs (Fig. 70). 
There is apparently a struggle but the parasite ultimately 
penetrates the host cell. The hypha is very much constricted at 
this point where it enters the cell but once in, it swells out into a 
tube as large as the normal hyphae of the intercellular spaces. 
It now begins to branch profusely and almost fills the entire 
host cell with short hyphae. The host cell nucleus is frequently 
enclosed in a tangled knot formed of these haustorial hyphae 
and as Raciborski (34) noted is hypertrophied. One haustor- 
ium is found in a single cell and the absorbtion of material by it 
is continued until the cell is dead. 
There are two nuclei in these branches that form the young 
appressorium and this number is maintained in the mature 
haustorium. They lie in the swollen ends of the appressorium 
(Fig. 70) and in the stalk of the haustorium just after it has 
entered the cell but has not started to branch (Figs. 64 & 65). 
While they may be seen taking other positions this location in 
the neck of the haustorium is probably the most favorable for 
their functions in relation to the entire haustorium. As noted 
before they take this same position in Urocystis Anemones. 
THEORETICAL DISCUSSION. 
The similarity of the promycelium which comes from the 
chlamydospores of the smuts to that which comes from the 
teleutospores of the rusts has been the principal reason for as¬ 
suming as Brefeld (6) has that the two groups are closely re¬ 
lated. While this promycelial tube is always divided into four 
cells by three transverse walls in the rusts and the number of 
6—S. & a. 
