Anatomy of Solenostelic Ferns: /. L ox soma, 75 
later on, does no more than quote Mettenius, and then com- 
pare the structure of the vascular system to that of Marsilea . 
No mention is made at all of the anatomy of Loxsoma by 
Prantl in his paper on the Hymenophyllaceae , and De Bary 
( 1 . c. p. 284) only refers again to Mettenius, at the same time 
regretting the lack of information concerning the nature of 
the foliar gaps in the tubular bundle. Finally, Giesenhagen 1 
confuses the correct opinion hitherto held regarding the 
vascular system, by speaking of it as a central collateral or 
concentric bundle ; he also refers incorrectly to the structure 
of the cortex. 
As regards the external morphology little additional infor- 
mation can be given. The rhizome is cylindrical and fairly 
stout (5-6 mm.). It creeps upon the surface of the soil, 
bearing erect leaves some two feet high, at intervals of about 
an inch. The leaves are situated on the upper surface of the 
stem, apparently in a single row, but alternating slightly on 
either side of the median line. They arise in acropetal 
succession. The stem is said to branch, but my specimens 
did not furnish an example. There are no localized points of 
departure for the roots, which arise irregularly upon the 
under surface and sides of the rhizome, both at the nodes, 
and also along the internodes. The leaves are highly dis- 
sected, and perfectly smooth and glabrous. On the stem and 
the base of the petiole (which is not articulated onto the stem) 
are a number of slight emergences which form the bases of 
awl-shaped structures more fitly described as hairs than as 
paleae. They are three or four cells thick at their base, but 
terminate in a single cell-row (5-12), the last cell of all being 
conically pointed. The walls are but little thickened and are 
coloured brown. 
The Stem. 
In a transverse section taken through an internode in a 
fully differentiated region of the stem, the vascular system 
is easily distinguished by the naked eye as a thin, perfectly 
1 Die Hymenophyllaceen, Flora, 1890. 
