A. C. Seward . 
44 
Botany 1 ” illustrating the structure, as seen in a transverse section, 
of the tissue between the secondary xylem and the inner edge of 
the region, which is described by Mr. Hill and myself as the 
secretory zone. In Dr. Scott’s figure the tissue immediately beyond 
the secondary wood is labelled phloem (“ ph ”); this is a zone 
about twelve cells in width ; beyond this ‘ phloem ’ one of the large 
leaf-traces occupies the rest of the figured portion of the section. 
The Dalmeny stem is fortunately preserved in wonderful perfection, 
and by means of transverse and longitudinal sections (figs. 1 and 2) 
Figure 2. Lepidodendron Wunschianum. 
Longitudinal Section. T, small tracheal and partially developed xylem 
elements; C, Meristematic Zone ; S, Secretary Zone. 
it is easy to make out the structure of the tissues between the 
xylem and the outer edge of the secretory zone. The tissue which 
Scott designates phloem is the same as that described as the 
me istematic zone in the original account of the stem 2 , and shown 
in figures 1 and 2, C ; the latter designation I believe expresses 
its true function. A few of the elements next the outermost 
secondary xylem are shown by longitudinal sections to be partially 
developed thin-walled tracheids(figs. 1 and 2, T)\ the active region 
1 Scott, 1900. Fig. 52, p. 131. 
2 Seward and Hill, 1901, p. 914; PI. II., fig. 10, cm, PI. III., figs. 
16 and 19 cm. 
