1897] BRIEFER ARTICLES 371 
growth of a bud and of any of its coverings from the moment of 
their origin as papilla on the side of a growing-point, by the branch 
and the part of the petiole opposite it, than by the thinner, 
weaker, and really more distant opposite sides of the more or less 
clasping concave petiole. Examination shows that the outermost bud 
scales of all the lateral buds of this little tree, whether these buds are 
borne on the branches with paired leaves or on the one with leaves in 
whorls of three, are invariably opposite the spaces between branch and 
petiole, only the bud scales of the second and next inner pair being 
opposite the branch and petiole. Similar examination of the terminal 
bud of a branch with paired leaves shows that its outer pair of bud 
scales are alternate with the preceding pair of leaves, and its paired 
bud scales are regularly alternate, suggesting the regularity in arrange- 
ment of the parts within, and promising a continuance of the regularity 
in the branch which will develop therefrom next year. 
On the other hand, the terminal bud of the one branch bearing its 
leaves in whorls of three has bud scales in whorls of three, the scales 
of the outer whorl alternating in position with the three leaves imme- 
diately behind this terminal bud, the bud scales of the succeeding 
whorls alternating regularly, and thus suggesting the same arrangement 
for the parts within, and prophesying a continuance of this arrange- 
ment of leaves on the nodes to be separated by growth of the inter- 
nodes, and on the nodes to be formed, next season. 
It seems to me, therefore, that in this little tree we have not only 
an interesting case of variation, but also an illustration of those influences 
— be they merely mechanical, as Schumann’ would claim, or due rather 
to the arrangement of the deeper-lying conducting-tissues and hence 
connected with nutrition — which, if they do not altogether control, at 
least Strongly influence the arrangement of the leaves and other struc- 
tures formed at successive nodes. I am unable to discover any indi- 
‘Cations of what might have caused the different leaf-arrangement in 
the bud from which the present branch bearing leaves in threes has 
developed. It is of course easy to speculate as to possible causes, and 
Perhaps if the branch were cut off, and examined microscopically at the 
©, evidences of the cause of the present difference might be found ; 
ut there are reasons which seem to me sufficient, for allowing this 
_ branch to grow on unmeddled with. We have then the variation, its 
“use being unknown. In the regular alternation of the leaves and the 
__ *Morphologische Studien, Heft I: Die Blattstellungen in gewundenen zeilen. 
