146 Kleinere Mitteilungen. 
borated by that means, since the increased-apecitity does not of itself 
appear in any irregularly arbitrary number but is limited in its number, 
so that a definite quantity of some definite measurements continually 
makes itself evident. The top for 12% cm for instance, repeats itself in 
the branch-pairs N° 7, 24 and 30. The apex of I4 cm repeats itself in the 
branch-pairs Ne 15, 18, 27, 30. Moreover, the same apices occur again and 
again. I have now isolated some very striking examples, but the pheno- 
menon is practically confirmed by all branch-pairs with regard both to 
leaf-length and leaf-breadth. It would appear that there is a clear proof 
to be found in these data that in one tree both more length- and more 
breadth qualities are present, and that these results are manifested over 
and over again in a single tree. When one begins to perceive the existence 
of a vast number endowed with the same property, the following con- 
clusion must be arrived at. The phenomena of plant modifications 
occuring through transit under varied conditions, is interpreted as a certain 
plastic capacity of the properties, reacting differently under different 
circumstances. BAUR developed these views in a very happy and in every 
sense suggestive manner in his well known book. Now, this plasticity is 
not easy of representation, and it may be a precursor, to give (in difficult 
cases) to the properties some “higher qualities” through which this con- 
ception, destined as an elementary one, becomes “a something” of the 
“higher order”, by means of which, phenomenon can be explained, when 
no other way is open! I think, it is much more in accordance with 
the BAUR school of thought, to make use of the phenomena that there 
is an increased number of each quality in this very sense: that under 
different circumstances there are others of these increased pro- 
perties that become predominant. It is in the same line of thought, 
that possibly the chromatic adaptations of the cyanophyceae did not 
depend on an actual colour change occuring in the individual itself, 
but were derived from a still further development of diversely coloured 
ones existing previously (BAUR). Thus also morphological periodicity 
can be accounted for: changes in outward circumstances bring other (also 
previously existing) measurements of a property to expression or to predo- 
minance. 
S 4. 
Not only should the presence of more properties of length or breadth 
etc. of one particular organ be of signification for our view in the plants 
capacity of modification; but the habit of a plant is also dependant 
of the manner in which those further forms of a property are distributed 
over the whole plant. It is by no mere chance that the examples which 
I have given in this composition concerning the periodicity of leaf variation 
or of the analysis of leaf-forms in the two independant qualities length 
and breadth, are taken from Coffea Uganda. Just as sharply as in C. 
