Contributions towards a Knowledge of the Anatomy 
of the Genus Selaginella, Spr. 
Part V. The Strobilus. 
BY 
GERTRUDE MITCHELL, B.Sc., 
Isaac Roberts Research Scholar in Botany, University of Liverpool. 
With Plates III and IV. 
[Preliminary Note. —In previous volumes of the Annals of Botany 
I recorded certain observations made by myself on the Comparative 
Anatomy of the stem, root, leaf, and ligule of Selaginella. Pressure of 
other duties has hitherto prevented me from recording observations on the 
anatomy of the strobilus, as I had originally intended to do. 
Since a very considerable amount of work has already been carried out 
on the structure of the sporangia and on the gametophyta by various in¬ 
vestigators, more especially by Pfeffer, Millardet, Belajeff, Lyon, Bruchmann, 
and Bower, the present paper cannot expect to do more than fill up, at least 
in part, some gaps left by these authors or confirm or controvert statements 
made by them. Being myself unable to devote the necessary time to the 
work, I asked one of my pupils, Miss Gertrude Mitchell, B.Sc., to undertake 
the investigation of the material I had collected. This she has done under 
my supervision, and the results of her work are now submitted. Miss Mit¬ 
chell has confined herself to a study of the structure of the strobilus and its 
parts from a morphological point of view, and has made no attempt to deal 
with the spore-contents, since the material available had, unfortunately, not 
been preserved with a view to cytological research. 
R. J. Harvey-Gibson.] 
I N the present paper I purpose recording some observations on the 
structure of the adult strobilus of the genus Selaginella , omitting, 
however, the gametophyta. The work, which was carried out in the 
Hartley Botanical Laboratories, University of Liverpool, was undertaken 
at the suggestion of Professor Harvey-Gibson, with the view of completing 
his series of papers dealing with the anatomy of the genus, and I am 
indebted to him for his help and advice during the prosecution of the work. 
[Annals of Botany, Vol. XXIV. No. XCIII. January, 1910.] 
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