82 BOTANICAL GAZETTE [SEPTEMBER 
Thamnochortus, the sheathing base of the scale leaf is described by 
VELENOVSKY (18) as surrounding the axis spirally, and, according 
to his fig. 358, its attachment forms more than two complete turns 
round the axis. Both sheath and narrow, flat limb of Restio trem- 
ulus are fibrous (fig. 1.B, C), and toward the apex of the limb 
there is a marked increase in the lignified and sclerised tissue 
(fig. 1D). The leaf of Leptocarpus peronatus Mast., with its 
sheathing base and limb reduced to a mucro, is represented in fig. 2. 
In the case of Elegia deusta Kth. the leaf apex is more solid, and 
includes a ring of bundles (10, fig. 5 A, B). 
Centrolepidaceae 
The leaves of the Centrolepidaceae are usually small, with a 
sheathing base and an awl-like or threadlike limb. Gaimardia 
australis Gaudich. (fig. 5 A-C) may be taken as an example. 
There is a sheathing leaf base and an awl-like limb, traversed by 
three bundles inclosed in fibrous sheaths. The leaves of this 
family may be of a more reduced type, however, as in Centrolepis 
aristata R. and S. In this plant I have found one bundle, 
traversing both sheath and limb (fig. 11 B, C). Gorse (13), 
on the other hand, describes and figures the leaf anatomy of this 
species as belonging to an extremely reduced ensiform type, with 
a second bundle above the median bundle, resulting from the fusion 
of two laterals. Although I have not found this structure in the 
only two foliage leaves which I was able to examine, I have seen it 
in two of the bracts from the base of the inflorescence (6, fig. 11 A). 
These bracts are well developed structures with a sheath and limb, 
closely resembling the foliage leaves. 
Mayacaceae 
The very delicate leaves of the single aquatic genus Mayaca, 
of which this family consists, are traversed by a single vascular 
strand (fig. 27. A). Several species figured in the Flora Brasiliensis 
(17) have a bifid leaf apex, such as is shown here for M. fluviatilis 
Aublet (fig. 278). It will be seen that the vascular bundle (vb) 
takes no part in the bifurcation, but terminates below the fork. 
