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the upper part of the root showing a complicated parenchyma 
structure due to root-contraction. 
3. The position of the leaves in the bud is a peculiar one 
and may be called alternating aestivation. 
4. There is no cauline stele even in the adult plant. 
5. The pith is not intra-stelar, but ground tissue enclosed 
between the leaf traces. 
6. No leaf gaps or root gaps could be detected. 
7. The general structural resemblance to Osmunda is more 
apparent than that to the Marattiaceous ferns. 
VE 
Botrychium virginianum, a form belonging to the subgenus 
Osmundopteris, has been investigated by Campbell (9) and 
Jeffrey (19). The origin of the vascular system has been 
investigated by Campbell (9). Very young plants, in which 
the first leaf was not yet expanded, were sectioned. The vas- 
cular bundle of the first leaf was just starting its development 
but it did not join as yet the main vascular tract. The trace 
of the first root joined the trace of the cotyledon and the two 
traces enclose a part of the ground tissue; the pith is not of 
stelar origin. The second root joined the vascular tract lower 
in the series. There is no trace of a cauline stele. 
The usual endophyte 1S present in the root, and peculiar 
cells are found on the ventral epidermis of the cotyledon. 
These cells stain brownish with vesuvin, and give a violet 
precipitate with iron chloride. The existence of tannin cells 
in this species, even in this genus, has been hitherto overlooked. 
B. virginianum shows the following characteristics : 
1. In the young sporeling there is no real cauline stele. 
2. The intra-vascular medulla is a part of the gound tissue. 
3. Tannin cells are probably present in the ventral epider- 
mis of the cotyledon at a very young stage. 
