544 Bancroft. — A. Contribution to our 
(Text-fig. 7). Formation and separation of the two steles are similar to the 
processes described for (3 stems ; below the level of complete separation, the 
single protoxylem group of the branch may divide once or twice (PL XXVI, 
Fig. 5; Text-fig. 7). 
Text-fig. 8. Diagrams of the stele; a series of sections taken through about if inches of 
a /3 stem, showing a ‘dichotomy’ in which the two branches are equal, and also the emission of 
a monarch foliar-trace. Compare the size^of these steles with those of a stems, drawn to the same 
scale, x 35. (From series K21, stem C, University College, London.) 
In branching a stems, although the two products are similar in struc¬ 
ture, one is usually smaller than the other (PL XXVI, Fig. 5; Text-figs. 1 
and 7); indeed the division can hardly be termed ‘ equal especially 
as only one of the several original protoxylem groups participates in branch 
