Lew ton- Brain . — Cor dy ceps ophioglossoides [Ekrk), 529 
root, the Fungus would seem to be dominant. My observa- 
tions do not show whether or not the Pine gains any compen- 
sating advantage for the loss which it undoubtedly sustains 
through the presence of the Elaphomyces hyphae. Certainly 
the roots have the appearance of suffering from the attack 
of a true parasitic Fungus, and it is difficult to imagine such 
a cortex as shown by them being of any service in the trans- 
port of nutrient material to the stele. 
I must now briefly describe other appearances presented 
in the Pine roots, by apparently the same Fungus. 
When sections were taken of the main rootlet they showed 
that no external fungus-sheath was present. The root, how- 
ever, was not free from the Fungus ; in many of the cortical 
cells the cell-cavity was filled with a pseudoparenchymatous 
network of hyphae (Figs. 29, 30). The outer cortical cells 
appeared to be first attacked, but the Fungus afterwards 
extends throughout the cortex, and in many cases the net- 
work was to be seen even in the cells of the endodermis. 
The walls of the cortical cells are fairly thick, some of these 
cells, as also some of the parenchymatous cells of the stele are 
filled with dark-staining substance (Fig. 29), similar to that 
shown by the cells of the cortex in the other roots as men- 
tioned above. There is certainly a considerable difference 
between these hyphae and the intercellular network of the 
smaller rootlets, but there seemed no trace of the presence of 
another Fungus, and I myself am convinced that both sets 
of hyphae belong to Elaphomyces variegatus. 
Another appearance presented by this mycorhiza was only 
seen by me in one series of sections. It here showed one 
of the main rootlets of the mycorhiza, and arising from this 
a smaller one. Both were covered with a fungus- sheath 
which was continuous over the point of origin of the secondary 
rootlet. The smaller rootlet showed the younger stage of the 
intercellular network. The larger rootlet on the contrary 
showed nothing of this, the walls of the cortical parenchyma 
were thickened and quite normal (Fig. 31). But in many 
of these cortical cells were seen bundles of fungal hyphae 
