66 
F. E. Weiss. 
Nothing can be seen in them that could be definitely identified with 
fungal hyphae, but if, as is suggested, the fungus was of Chytri- 
diaceous affinities the mycelium may have been of a very slight and 
transitory kind and would very probably not have been preserved. 
At the outside of the dark patch we see another group of cells 
which show signs of having undergone a process of division (o.s.t.) 
These, however, are more irregular in their arrangement than the 
cells of the inner secondary tissue; their cells are less flattened and 
have thicker walls At the side, however, indicated by the lettering 
(o.s.t., fig. 67) the secondary nature of the tissue is quite apparent. 
It seems to have taken its origin from the innermost layer of the 
outer cortex, which, as mentioned above, is of a more delicate 
character than the outer layers of that tissue. 
Text-Fig. 67. Enlarged view of a portion of the above rootlet containing 
the large hypertrophied cell h.c. The latter is widely open to the 
exterior and is seen to contain a spore-body. The oblique line across 
it is due to a crack in the matrix and is not a cell wall. 
o.s t., outer secondary tissue caused by divisions in the inner layers of the 
outer cortex. 
i.s.t., inner secondary tissue formed from the middle Cortex, and cutting off 
a mass of dead and disorganised cells. 
x y., xylem elements. 
i c., inner cortex, m c., middle cortex, o.c., outer cortex. 
