363 
b) Two leaf traces, arising from the sides of the gap; Marat- 
liaceae. 
c) More than two leaf traces; Ophioderma, Cheroglossa, all 
the other ferns. 
We see that in this respect Botrychium obliquum, and sila- 
eifolium, the large leaves resemble in form the Osmundaceae 
and Euophioglossum while the “lunaria” group shows im B. 
simplex and B. neglectum connecting links between the former 
forms and the Marattiaceae. B. virginianum shows also a division 
of the leaf trace in the older leaves (Campbell). It seems, there- 
fore, that tannin cells and reduplication of the leaf trace, sooner 
Fig. 41. Fig. 42. 
or later in ontogeny, go together and show a resemblance to 
the Marattiaceous condition. 
This condition was much more pronounced in the root 
traces of two other plants of B. neglectum (Fig. 42). Here the 
root traces originated from the fusion of two lateral traces at 
the margins of the gap. This is not always the case, however, 
the normal ‘‘simplex’”’ condition (Fig. 41) bein represented in 
the majority of the cases. 
Returning to the reconstruction model Fig. 41, we may ask 
if all the vascular tissue in this case is of phytonic origm. In 
order to determine this, transverse sections, taken immediately 
