Studies in the Morphology and Anatomy of the 
Ophioglossaceae. 
I. On the branching of Botrychium Lunaria, with notes on the 
anatomy of young and old rhizomes. 
BY 
WILLIAM H. LANG, M.B., D.Sc., F.R.S. 
Barker Professor of Cryptogamic Botany in the University of Manchester. 
With Plates XX and XXI and fourteen Figures in the Text. 
I N these studies some results obtained by the re-investigation of examples 
of all three genera of the Ophioglossaceae will be described. The 
affinities of this group of plants have long been a matter of doubt and 
dispute, but of recent years the evidence for the early view that the 
Ophioglossaceae are a primitive group of Ferns has been greatly strengthened. 
This has resulted less from their further study than from the increase of our 
knowledge regarding other primitive Ferns, both extinct and recent. While 
my study of the Ophioglossaceae has led me to hold this view as a highly 
probable working hypothesis, the object of these papers is not to expound 
it, but to examine in detail some facts which must be taken into considera- 
tion, whatever conclusion as to the phylogeny of the group is ultimately 
arrived at. It is hoped that this will be of assistance to investigators who 
are engaged in the study of extinct Ferns. The full discussion of results 
will be deferred until the last of these studies, but the bearing of particular 
points of interest will be briefly considered in each paper. 
External Features. 
The general morphology, anatomy, and life-history of Botrychium 
Lunaria are well known from the earlier researches of Braun, Roeper, 
Hofmeister, Russow, Holle, and others, supplemented by the study 
of various points of detail by later investigators. Familiar as our native 
species of Botrychium is in laboratory work, it is difficult to collect a com- 
plete account of the anatomy of its rhizome from the literature. More 
[Annals of Botany, Vol. XXVII. No. CVI. April, 1913.] 
