Boodle — Anatomy of the Schizaeaceae . 373 
typical of the rhizome of Lygodium is attained in the seedling 
without any intermediate more complicated structure. Hence 
there are no grounds for assuming a reduction to have taken 
place. 
With regard to the first and second leaf-trace of the seed- 
ling, although they pass off from the stele as collateral 
bundles, their phloem, though only containing a few sieve- 
tubes, spreads towards the inner side as they pass through 
the cortex of the stem, so that they become concentric or 
very nearly so, and the same structure appears to be con- 
tinued in the petiole. 
The leaves are radially arranged on the upright stem of the 
seedling, the dorsiventral arrangement of the mature plant 
beginning after the first dichotomy of the stem. 
SCHIZAEA, habit. 
The stem of Schizaea digit at a, Sw., may be erect or ob- 
liquely ascending, or often in old plants the lower part of the 
stem is erect, and the upper part ascending or even horizontal. 
The leaves are crowded on the stem, and the roots attached 
between them ; the phyllotaxy is difficult to determine and 
probably variable, but in some stems it appeared to be 
in places, but usually the orthostichies numbered more than 
three. In 5. fistulosa , Labill., the leaves are, at any rate 
sometimes, dorsal and distichous. The leaves of 5. digitata 
are narrow-linear, and grass-like, often over a foot in length. 
The petiole is triangular in section, and passes gradually into 
the lamina, which is flattish only in its upper region, where 
it shows a prominent midrib on the lower side. The leaves 
of certain other species are much broader and are dichoto- 
mously forked. 
Schizaea, stem. 
In the rhizome of Schizaea digitata, Sw.. the stele shows 
a marked difference from that of Lygodium. The dis- 
tinguishing character is that the xylem consists of tracheides 
with usually no parenchyma among them, and forms a ring 
