750 Bancroft.—On the Xylem Elements of the Pteridophyta. 
support Halft’s views as to the tracheidal nature of the xylem elements 
of the Pteridophyta in general. 
III. Microscopical Examination of Material. 
1. Material was chosen with a view to extending observations to the 
lower Filicales, Marattiales, Psilotales, and to other members of those 
groups representatives of which have already been investigated by Halft. 
The types examined include:— 
Equisetmn limosnm 
Lycopodium alpinum 
L. Phlegmaria 
L. selago 
Selaginella Kraussiana 
S. Wildenovii 
S. Martensii 
Psilo turn triquetrum 
Tmesipteris tannensis 
Angiopteris erect a 
Marattia lax a 
M. elegans 
M. fraxinea 
Osmunda regalis 
O. Claytoniana 
O. cinnamomea 
Todea hymenophylloides 
Lygodium scandens 
L. dichotomum 
A neimia fraxinifolia 
Mohria cajfrorum 
Gleichenia circinata 
Matonia pectinata 
Trichomanes radicans 
Polystichum angidare 
Blechnum brasiliense 
Aliosoms crispus 
Asplenium bulbiferum 
Phlebodium glaucum 
Marsilia Drummondii 
2 . Fixing.—The different solutions used for fixing the material 
were:— 
Alcohol (93 % or 95 %). 
Farmer’s fluid (acid-alcohol). 
Jeffrey’s solution. 
aerial stem 
stem 
» 
» 
>) 
» 
rhizome to aerial stem. 
)J 55 )) 
petiole 
>5 
)> 
root and petiole 
petiole 
rhizome and petiole 
rhizome 
rhizome and petiole 
petiole 
5 > 
•> 
)> 
rhizome 
rhizome and petiole 
petiole 
>> 
55 
rhizome and petiole 
rhizome 
» 
