Evolution of Branching in the Filicales. 
5 
A 
Hymenophyllacese 
Zygopteris Cheiropleuria 
B 
Marsiliace® 
Metaxya Lophosoria 
Cibotium Alsophila Aspidiuro 
t *: 
Nephrolepis 
Fig. 1. Diagrams to illustrate the vascular relations between branch 
and main axis. Xylem black, phloem dotted. The thinner lines in D represent 
the medullary strands. Further explanation in the text, p. 4-9. 
the proximal portion of its strand “adherent” to the trace of the 
associated leaf, which belongs to the main axis. 1 The strand under 
discussion would thus have a composite nature, and we may extend 
1 A view which we owe originally to Dr. Scott, (Annals of Botany, 1912, 
Vol. XXVI, i. p. 59) but which was rejected by him in preference to the leaf- 
ti;ace theory. The question is further dealt with on p. 19 of the present paper 
