in the ‘ Seedlings ’ of Certain Leptosporangiate Ferns . 373 
the external phloem. The xylem was thus divided into two portions, and 
the appearance of another parenchymatous band, almost at right angles 
to the first, divided the xylem into three portions, the whole strand for 
several successive sections almost exactly simulating the appearance of 
a triarch root. At a slightly higher level the two bands had taken 
up a more or less central position in the xylem as two parenchymatous 
islands, one gradually dying out, the other maintaining its size, and, after 
one or two transitory connexions with the external phloem, appearing with 
a central strand of a few sieve-tubes. This occurred just before the first 
leaf-trace, which was separated from the cauline strand as a sector of 
vascular tissue by the development of parenchyma cells between the 
external and internal phloem. 
In other plants similar variations occurred, all obviously connected 
with the parenchymatous nature of the xylem. A description of these 
variations, though interesting in itself, is unnecessary. 
Lomaria Spicant, Desv. 
The writer is indebted to Mr. T. G. Hill for an abundant supply 
of material of this plant. The transition from root to stem is somewhat 
rapid, but takes place in the usual manner. The root is diarch, and the 
protostele of the stem soon possesses a few parenchymatous cells at its 
centre. Just before the exit of the first leaf-trace one or two sieve-tubes 
appear in the parenchyma, so that at this stage we have, as before, a central 
strand of phloem surrounded by xylem, which, in its turn, is ensheathed in 
a cylinder of phloem. The most striking feature of the anatomy of the 
younger plants is the thick- walled character of the cells of the fundamental- 
tissue. The pitted walls are deep brown in colour, and the cell contents 
consist largely of densely staining tannin. The fundamental and vascular 
tissues are thus sharply contrasted. 
The first two or three leaf-traces leave the amphiphloic protostele 
in a perfectly normal way, the external and internal phloem becoming 
continuous at the gap, which is merely bridged by the somewhat small- 
celled endodermis. 
At the level when the endodermis bridges the third or fourth leaf-gap, 
and while the latter is still unclosed, one or two cells appear in the central 
phloem in the neighbourhood of the gap. The cells have thickened, 
yellowish, glistening walls and are thus readily distinguishable from the 
phloem. These cells, as we pass upwards, are immediately succeeded 
by a few others which have all the characters of the fundamental-tissue, 
viz., hard, thick, pitted walls, and tannin-impregnated contents. The most 
interesting fact, however, is that this group of fundamental-tissue cells is 
surrounded by an endodermis exactly resembling the outer endodermis in 
its small narrow cells, and which would readily escape anything but careful 
