PREFATORY NOTE TO TWO UNPUBLISHED PAPERS 
BY THE LATE PROFESSOR D. T. GWYNNE-VAUGHAN. 
Among the research notes of Professor Givynne-Vaughan on the 
vascular system of the Pteridophyta two investigations were in a sufficiently 
forward state to justify publication. 
In both cases the idea of the research was clearly defined, full notes of 
the observations were available, and the slides were annotated with a view 
to the preparation of figuresi We have thus found it possible to present 
the results almost entirely in the author’s own words, and to add illustra- 
tions in accordance with the original intention. 
The paper on ‘The Anatomy of the Leaf in the Osmundaceae* 
existed as a preliminary draft, and it is published substantially without 
alteration, but with the addition of photographic illustrations. This is 
the paper referred to in Part V of the series of memoirs on the fossil 
Osmundaceae. 
In the case of the investigation on ‘ Some Clirnbing Davallias and the 
Petiole of Lygodiurn ’ only the introduction had been drafted. This con- 
tains, however, a clear statement of the object of the work, and the facts 
extracted from the full notes on the several species become in its light 
a connected story,; It is from this point of view that we have included 
some already known facts as to Lygodiuin which were reinvestigated by the 
author for purposes of comparison with Davallia. The notes include 
a series of freehand pencil sketches, photographs of some of which, after 
being traced with Indian itik and bleached, are here reproduced as text- 
figures. We have supplemented them by photographs of a few of the more 
important sections. 
Had these papers been completed by Professor Gwynne-Vaughan the 
theoretical bearings of the facts would doubtless have been more fully 
developed and placed in relation to the work of other investigators. We 
have preferred to make no attempt to go beyond what was actually set 
down except in respect of the few notes enclosed in square brackets and 
the description of the figures in the text and plates. The course we have 
adopted avoids the disadvantage of any attempt to rewrite the papers. 
[Annals of Botany, Vol. XXXI. No. CXX. October, 1916.] 
L 1 
