Boodle. — Anatomy of the Schizaeaceae. 393 
finally abuts on the mass of sclerotic tissue occupying the 
centre of the stem. No axillary pockets are present. The 
leaf-trace on entering the stem has the form of a low curved 
arch, then becomes U-shaped as it passes inwards, and fuses 
at its ends with two adjacent steles in much the same way as 
in Anemia Phyllitidis. a , a are two steles, which will fuse 
with the leaf-trace opposite them ; the larger one corresponds 
with the long-flat stele described in Anemia. After fusion 
the bundle has a conspicuous knob at each end (Fig. 35, b.)> 
as in Anemia , and soon becomes less curved, and finally 
the whole has an oval outline. The changes with regard to 
the phloem and protoxylems are nearly the same as in 
Anemia Phyllitidis , but the leaf-trace in passing through the 
cortex often has five protoxylem-groups, one median one, 
which includes spiral elements, and is a little earlier than 
the others, two close to the ends of the xylem-arch, and one 
about halfway up each arm of the xylem. This, however, 
sometimes occurs in Anemia . The steles are smaller than in 
Anemia Phyllitidis , but have a similar structure. The trach- 
eides are scalariform, and the sieve-tubes sometimes have 
very prominent thickenings between the sieve-plates. Fig. 37 
is a longitudinal section of a stele in the young rhizome, at 
a level where hardly more than protoxylem was differentiated. 
It shows two sieve-tubes (phi) separated from one of the 
early tracheides by conjunctive parenchyma. 
Mohria, petiole. 
The petiolar bundle of Mohria caffrorum with the adjacent 
group of sclerotic tissue (sc.) is shown diagrammatically in 
Fig. 36. The distribution of the phloem is shown by the 
shading. The xylem forms an arch with hooked ends, and 
there are three protoxylem-groups : one median, and one 
just above each hook. They are on the inner surface of 
the arch, and each is accompanied by cavity-parenchyma. 
Excluding the sclerotic tissue, which does not belong to the 
bundle, the structure is almost indistinguishable from that of 
