443 
Seedling Structure of Gymnosperms. III. 
part, four bundles arranged in a row parallel to the greatest width. ... In 
the lower part of the lamina of the cotyledon and in its stalk, besides the 
row of four or five bundles, there are two or three others towards the ventral 
side, which may be orientated like those of the normal row or may lie side- 
ways/ These inner bundles, on tracing them upwards, lose their phloems, 
and their xylems become united each with one of the normal strands. 
Towards the basal region the majority of the strands become concentric, 
a fact which Worsdell regards as of considerable phylogenetic importance. 
Matte 1 found four or five normal bundles in each seed-leaf in addition 
to a few strands towards the ventral surface. As regards these last, Matte 
does not find any phloem, £ ils se montrent simplement constitues par des 
vaisseaux isodiametriques tres larges, en groupes plus ou moins compacts qui 
reunis vers le haut aux faisceaux voisins de 1 ’arc normal . . / Further, 
he disagrees with Worsdell regarding their significance. The strands here 
referred to are wanting in our material ; they, therefore, are probably nothing 
more than individualistic variations of no theoretical import in the present 
connexion. 
Passing on to our own observations, it was found that in one case the 
larger seed-leaf had five strands which, by the time the cotyledonary node 
had been reached, were reduced to three by the fusion of adjacent traces, 
while the smaller cotyledon had two throughout ; in another example the 
smaller seed-leaf had two vascular bundles and the larger three towards the 
apex, but another was differentiated at a lower level which, at the cotyle- 
donary node, fussd on to its nearest neighbour. The following description 
of the transition-phenomena is based upon the latter seedling, owing to the 
fact that the former one was so young that the vascular bundles of the 
hypocotyl were insufficiently differentiated. 
Transition. 
Matte 1 has described some phases of the vascular rearrangements in 
the transition region. Our results are in accordance with his so far as the 
treatment coincides. At the cotyledonary node five traces enter the axis 
(Diagram 3, Fig. 1), two from one seed-leaf and three from the other. These 
gradually pass to the central region of the axis, much more slowly than in 
Macrozamia , where the plumular bundles form conspicuous objects (Dia- 
gram 3, Fig. 2). Terming the seed-leaf-traces a , b , c, d , and and the 
plumular traces p. i y p. 2 . . . ; the strand d passes between p. 1 and p. 2 
and fuses with them, and, at a slightly lower level, the trace a effects 
a junction with p. 4 (Diagram 3, Fig. 3). The trace e entirely fuses with 
d (Diagram 3, Fig. 4), there is then a general union of the remaining bundles, 
which leads to the formation of a horseshoe-shaped vascular cylinder as 
viewed in transverse section (Diagram 3, Fig. 5). During these changes the 
1 loc. cit. 
