A. G. Tansley. 
236 
of higher leaves. Segments from the third cylinder fill up the gaps 
in the second in the same way, and so with the successive inner 
cylinders. 
Fig. 79. Angiopteris cvccta. Part of vascular skeleton of dorsal side of 
stem seen from without, to show the rapid passing out of strands from inner 
cylinders to fill the gaps made in the outer one by the departure of the leaf- 
traces. a, b, c, d, e, f t designate the strands belonging to different traces. 
R , root-steles. The outer cylinder is left white ; the parts of the second 
cylinder shown are shaded ; the third cylinder, only represented in a small 
part of the figure, is black. After Shove. 
A 
B 
Fig. 80. Angiopteris evecta. A.—Vascular skeleton of leaf-base. 13.— 
Transverse section of base of petiole, a, b, lateral groups of strands of the 
leaf-trace, e — e, external strands forming the abaxialarc of the trace. i—t, 
internal strands arising from e—e and multiplying by branching, k - k, strands 
derived directly from the second cylinder. From Mettenius. 
