426 Boodle and Hiley. — On the Vascular Structure of 
Branching of G. Pectinata. 
In the rhizome of G. pectinata there are two kinds of branching, one 
monopodial, the other apparently dichotomous. The latter type appears 
not to be known to occur in the rhizome of any other species of the genus. 
Fig. 3. Gleichenia pectinata. Transverse sections showing dichotomous branching, c. cortex ; 
ep. epidermis ; ext. end. external endodermis ; ext. ph. external phloem ; int. end. internal endo- 
dermis; int. ph. internal phloem ; m. medulla; xy. xylem. x about 13. 
In G. pectinata monopodial branching always takes place in the vertical 
plane, the branch being uppermost, and all the protoxylems of the branch 
owe their origin to the upper protoxylems of the original stele (Plate XXIX, 
Fig. 8). Two protoxylem-groups of the upper kind are left in the lower 
