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Gwynne- Vaughan. — On the Anatomy of 
petiolar branches will probably prove to be characteristic of the Marattiaceae 
as an order, and I agree with them in regarding it as a distinction between 
this order and the leptosporangiate Filicineae. As regards the Ophio- 
glossaceae, Helminthostachys seems to present a parallel case ; for each of 
the first pair of pinnae certainly receives branches from the internal strand, 
although the greater portion of it passes out into the fertile spike. 
The Structure of the Stipule. 
The wings of the stipule of Archangiopteris contain a number of small 
anastomosing vascular strands arranged in a row with their protoxylems 
facing adaxially towards the median plane of the petiole. There are also 
a few additional strands in the upper part of the stipule lying on the adaxial 
side of the main row, and facing in the opposite direction. They are all 
derived from about three main branches which arise from the strands at 
the adaxial corners of the petiolar curve. The transverse commissure has 
no vascular supply at all in Archangiopteris , but in K aulfussia it contains 
a row of strands facing away from the petiole. 
In Archangiopteris a small group of cells having the appearance of an 
arrested meristem is to be found at the bottom of a little pit situated at the 
base of the stipule near the margin of the wing, but slightly over on to 
the adaxial surface (about the point x in Figs. 3 and 4). A similar group 
occupying the same position is also present in Kaulfussia (x in Fig. 5). It 
is here rather more highly developed, and sometimes forms a definite 
projection into the bottom of the pit. In both genera there is a broad 
curved vascular strand in the stipule which is derived from the corner 
strands of the petiolar curve and terminates just below this meristematic 
group. The whole structure clearly belongs to the petiole and not to the 
stem. These structures are to be found on all the leaves, even the young 
ones, and they are no doubt to be regarded as arrested apices of dormant 
adventitious buds, and the ‘ stipular budding ’ that is well known to occur 
in the Marattiaceae is probably to be accounted for by their belated 
development 
Histology. 
Archangiopteris , as regards the minute structure of its tissues, agrees 
almost exactly with the descriptions given for the related genera by 
Miss Shove, Farmer and Hill, and Brebner 1 . The protoxylem elements 
1 R. F. Shove, ‘ On the Structure of the Stem of Angiopteris evecta / Annals of Botany, 
vol. xiv, No. lv, p. 497, 1900. Farmer and Hill, ‘ On the Development and Structure of the 
vascular strands in Angiopteris evecta , and some other Marattiaceae,’ Annals of Botany, vol. xvi, 
No. lxii, p. 371, 1902. Brebner, 1. e, 
