386 Boodle . — Anatomy of the Schizaeaceae. 
one. The structure resembles th o. solenostelic type 1 as defined 
by Gwynne-Vaughan (’01, p. 73), while Anemia Phyllitidis is 
dialystelic. The cortex of A. mexicana consists of brown 
elements, which are slightly sclerotic in the outer half, and 
strongly sclerotic in the inner half. Fig. 38 represents the 
stelar ring of this species, which is bounded by an outer and 
inner endodermis. Owing to the rupture of the radial walls 
of inner and outer endodermis, the cortex and central ground- 
tissue which is sclerotic have broken away, and only the stelar 
ring is shown in the figure. It is about 1 mm. in diameter, 
and its structure is as follows : — the pericycle forms a layer 
2-4 cells thick on the inner and outer side ; there is an inner 
and outer layer of phloem, each consisting of a practically 
continuous layer of sieve-tubes, mostly one element thick. 
The sieve-tubes are rather thick-walled, and stain deeply with 
haematoxylene. A layer of conjunctive parenchyma separates 
the phloem on both sides from the xylem. The xylem-ring 
is about five tracheides in thickness. The tracheides are 
scalariform, and the larger ones are on the inner side, the 
smallest tracheides being at or near the outer side. This is 
seen in the small piece of the stelar ring shown in Fig. 39. 
A comparison of this figure with Fig. 40 shows that there 
is a close agreement in structure between the solenostelic ring 
of Anemia mexicana and the separate ‘steles ’ of the stem of 
A. Phyllitidis. In A. mexicana a spiral protoxylem-group 
which comes in with the leaf-trace is continued a short way 
down in the stem. The tracheides elsewhere in the stelar 
tube appear to be all scalariform. In this and other species 
of the same subgenus which were examined, only small pieces 
of dried material were obtainable, so the structure was not as 
fully investigated as was desirable. The petiole in this and 
the next species was not examined. 
A. adiantifolia has in its rhizome practically the same 
structure as A. mexicana . 
In A. coriacea , Griseb. 2 , the solenostele is less than \ mm. 
1 Leaving the behaviour of the endodermis at the node out of the question. 
2 In Hooker and Baker’s Synopsis Filicum (p. 433) the authors were inclined 
