79 
Eriksson. The observations of René Maire, in the Bulletin 
7, la Societe Mycologigue de F vance, 1901, with regard to the 
ife-history of Endophyllum sempervivi, are also to the point. . 
~ With regard to P. glumarum, no mycelium is developed until 
the following summer, in the month of July, when the Uredo 
spores are formed. Sections taken from an affected leaf 4 to 6 
st beyond the most external spore-bed, and treated 
in the same manner, show the mycelium to consist at first of 
masses of granular mycoplasm between the cells of the plant 
fig. 1,¢,t.u,f.11,¢). From these masses outgrowths take place 
which force their way among the cells (fig. 1, D, 2, f. 11, a). At first 
the granules are very small, but they soon increase in size. These 
elongated masses become invested by a very delicate membrane 
which thickens and eventually acquires a double contour. Septa 
now appear, and some of the granules become surrounded by 
aclearer area. hese changes are shown by t. i, f. 11, a, where 
an elongated mass is seen extending between the cells. Fig 1, £, t. . 
i. f. 14, shows a later stage, in which a double contoured mem- 
brane has invested such an extension. The granules are larger, 
many of them surrounded by clearer areas, and septation has 
commenced. 
More recently (Comptes Rendus, July 4, 1904), Eriksson has 
confirmed the above results with two or three species, viz., the 
crown rust of Rye (P. dispersa), and the yellow rust of Barley P. 
glumarum f. Hordet. With these he finds an extension of the 
plasmic masses takes place not only bciween the cells of the 
host plant, but, like other forms of protoplasm, it often occurs 
from cell to cell through the normal openings which exist in 
the cell walls. Thus those endohaustoria are produced in the 
cells, which he has designated special corpuscles. The fact 
that a parasitic fungus can exist in a protoplasmic form in the 
tissues of its host and only develop mycelium and spores under 
certain conditions of environment is an extremely important one 
and one which, if proved, will explain some of the unsolved 
mysteries connected with the life-history of the Potato disease, 
not to mention other epidemic plant diseases. That the subject 
is one worthy of study is shown by the fact that our distinguished 
Vice-President, Professor Marshall Ward (than whom no one is 
better able to elucidate the whole question), has undertaken a 
senes of investigations with regard to it—Kzing’s Lynn, 
September 14, 1904. 






