Anatomy of the Ophioglossaceae . /. 231 
rhizome (Text-fig. 12, h). Meanwhile several irregular groups of tracheides 
have developed in the tissue between the stele of the branch and that 
of the main axis. These tracheides, like the adaxial group left behind by 
the branch, soon die out. Before this happens, however, the latter group 
passes across and fuses with the inner group of tracheides. 
It is unnecessary to follow the stele of the branch in detail. It need 
only be said that the stele is small at its commencement, and does not 
exhibit the contraction or reduction shown by the former branch. The 
vascular relations of this branch to its subtending leaf-trace show a general 
correspondence with the branch previously described, but are less regular. 
In both these specimens the chief vascular attachment of the branch is to 
the adaxial side of the subtending leaf-trace, some distance above its 
Text-fig. 12. Series of transverse sections of the second branching specimen. Description in text. 
separation from the main stele. In the two specimens now to be described 
the attachment of the branch is deeper in the axil of the leaf-trace, and 
more closely related to the stele of the stem. 
The vascular relations were especially regular in the third specimen 
(Text-fig. 13 ; Phots. 35, 36). Here also the upper end of the main axis had 
been destroyed, and one axillary bud, a short distance behind the cut end, 
had produced a branch. As the subtending trace begins to leave the stele 
additional tracheides are evident to either side of the xylem, and practically 
connect the departing trace to the sides of the leaf-gap in the xylem (a). 
The additional xylem soon extends across the adaxial face of the leaf- 
trace ( b ), and the stele of the branch is organized from the first in this 
adaxial xylem (b-e). While this is going on, and even after the leaf-trace 
has departed ( e) f the xylem of the branch is connected by a tract of 
tracheides with the margins of the leaf-gap. The xylem of this branch, 
