Seedling Structure of Gymnosperms. IV. 327 
Inasmuch as Bower has described the structure of the foot and has 
considered its morphology very fully, there is no need for us further to deal 
with it in detail ; it, however, may be remarked that we look upon this 
structure as an outgrowth produced expressly to effect the removal of the 
reserve food materials, and that it has no phylogenetic importance. 
A short cotyledonary tube occurred in all examples of the species 
examined. 
With regard to the structure of the seed-leaves there is nothing of 
importance to remark upon. The young cotyledons have very little lamina 
and a well-marked midrib containing five vascular bundles, which in their 
structure resemble those of Welwitschia. The strands are endarch and 
collateral throughout the length of the cotyledon, and at the base they 
tend to fuse together, so that in G. scandens and G. moluccense , as far as has 
been seen, and in some examples of G. Gnemon , five strands may enter the 
axis from one cotyledon, and four from the other ; in other seedlings of 
Gnetum Gnemon five bundles enter the hypocotyl from each seed-leaf. 
Within the axis the bundles tend to fuse together, the extreme lateral 
strands of one cotyledon joining with the corresponding bundles of the 
other seed-leaf, but this again is not constant in all cases. 
Transition. 
At a level just below the cotyledonary node the bundles anastomose 
freely, and some, at any rate, of the xylem elements of these connexions 
are differentiated from the ground-tissue, and resemble the transfusion 
tracheides remarked upon above as occurring in the hypocotyl of Ephedra 
and Wehvitschia. In the case of G. moluccense , the anastomoses between 
the bundles of the cotyledons, the cotyledonary bud, and the plumule were 
of the greatest complexity, and the special tracheides were extensively 
developed. After these general connexions between the various traces have 
been made, six large bundles obtain in the upper part of the axis together 
with a few small intervening ones, ill developed and small at this level, but 
rapidly increasing in size and differentiation lower down ; also the larger 
strands branch and new ones may come into being between the pre¬ 
existing traces. Thus the number of bundles is increased, and throughout 
the greater length of the hypocotyl a varying number, about twelve to 
fifteen, occur in the species examined. 
In that part of the axis situated immediately above the foot, a reduction 
in the number of bundles is brought about by the union of neighbouring 
structures; several of those on the foot side of the axis enter the upper 
part of the sucker, and so supply it with vascular tissue as described by 
Bower. After having passed to the extremity of the foot these strands 
return along the lower side, and thus regain the axis. Of these bundles, the 
two last, on their arrival near the central region of the hypocotyl, are seen 
