704 Boodle . — Anatomy of the Gleicheniaceae . 
appear to be any immediate prospect of a definite solution 
to such morphological problems. 
Two genera only are included in the Gleicheniaceae: Platy - 
zoma , Br., and Gleichenia , Sm. ; the species, on which 
Stromatopteris , Mett., was founded, being classed by Hooker 
and Baker (’74) as a species of Gleichenia. By both Christ 
(’97) and Diels (’00) Platy zoma is included in Gleichenia , and 
according to the latter author Stromatopteris ranks as a genus 
distinct from Gleichenia. 
It is hoped to obtain further material of some of the 
species in which only small pieces of dried material were 
available, and to publish some additional observations together 
with those proposed in the case of the Schizaeaceae. 
Of the two genera, Gleichenia will be taken first, and the 
description will be divided into sections in the same way as 
in the last part of this paper (p. 359 of this volume). 
Below is a list of the species in which either rhizome, or 
petiole, or both were examined. This list is given here so 
that the specific names may be divested of their authors in 
other parts of the paper. 
Platy zoma microphyllum , Br. In the subgenus Eugleichenia, 
G. moniliformis , Moore, G. polypodioides , Sm., G. circinata , 
Sw., G. Boryi , Kze., G. dicarpa , Br. In the subgenus Mer- 
tensia , G. longissima , Bl., G. flahellata , Br., G. Cunninghami , 
Hew., G. pedalis , Klfs., G. cryptocarpa , Hk., G. revoluta , 
H. B.K., G. simplex , Hk., G. pubescens , H.B.K., G. flagellaris } 
Spr., G. vestita , Bl., G. pectinata , Pr., £. dichotoma , Willd. 
Gleichenia, habit. 
The stem, except in 6\ moniliformis , is a creeping rhizome, 
, bearing roots on its lower side and leaves on its upper side. 
The internodes are usually long, and the leaves, though 
sometimes apparently forming a single row, are in certain 
species tristichous, though with only a small divergence. The 
roots may be irregularly placed, or in rows (e. g. tristichous). 
The leaf generally has a long petiole, and the first division 
is dichotomous, dividing the leaf into two primary pinnae, 
