Anatomy of the Ophioglossaceae . /. 225 
may be in the case of a developing branch making special demands on the 
water-supply from the main axis. In Fig. 24 the lower region of the leaf- 
trace, which subtended the branch in the branching specimen, is shown in 
transverse section. In it a complete arc of pericyclic xylem has been formed 
on the abaxial side. This, as will be shown, was not continuous with the 
pericyclic xylem of the stem, and did not directly contribute to the supply 
of the branch. This description, along with the figures, will serve to put on 
record an anomalous development for which I know no parallel in the 
Filicales. 
Vestigial Axillary Buds and Branching of the Rhizome. 
The plants of Botrychium L unaria that come under observation are 
usually unbranched. In 1859, however, Roeper 1 described and figured 
rhizomes bearing numerous lateral branches, and in 1875 Holle 2 gave 
a brief account with a diagrammatic figure of the only branch he had met 
with. Bruchmann 3 states that he had found a dozen examples of branching, 
and that young plants appeared to be more liable to branch than older 
ones. He does not enter into the anatomy of the branched plants, but 
describes and figures the origin of lateral growing points. While regarding 
these as the initial stages of the development of branches, he makes no 
remarks on their frequency or their constant relations to the leaves. Bower 4 
placed Bruchmann’s observations on B. Lunar ia in relation to the axillary 
structures previously described in H elmint host achy s by Gwynne- Vaughan, 6 
and interpreted by him as vestigial lateral buds. It may be added that 
Velenovsky figures a branched specimen of B. matricariae folium, and that 
Campbell records a case of branching in B. lanuginosum due to the apex 
having been destroyed and two lateral shoots developed as adventitious 
buds. I have communicated a note on the branching of the Ophio- 
glossaceae to the Proceedings of the Manchester Literary and Philosophical 
Society, 6 and examples in all three genera will be described in these studies. 
The study of complete series of sections through small plants, and of 
transverse and longitudinal sections of older and larger rhizomes, has shown 
that a structure comparable to the vestigial bud of Helminthostachys is of 
practically constant occurrence in every leaf-axil of Botrychium Lunar ia. 
The position of these vestigial buds, wherever recognized, is indicated by 
the crosses in the stelar reconstructions (Text-figs. 3-8). In Botrychium , 
as in Helminthostachys , the structure is not obviously bud-like, but in both 
plants its nature is established by the occasional development of actual 
branches in the corresponding position. 
1 Bot. Zeit., xvii, 1859, P- 2 57 > Taf. XII. 2 Bot. Zeit xxxiii, 1874, p. 301, Taf. Ill, Fig. 4. 
3 Loc. cit, p. 226, Taf. II, Figs. 60-62. 4 Land Flora, p. 443, footnote. 
6 Ann. of Bot., xvi, p. 170. 6 Feb. 20, 1912, 
