In C.
montana it is confined to the main petiole, and has not spread to the
sub-petioles of the three leaflets; so it is with young plants of C.
calycina, but in older plants it spreads to the three sub-petioles.
In C. viticella the sensitiveness has spread to the petioles of the
seven leaflets, and to the subdivisions of the basi-lateral sub-
petioles. But in this latter species it has diminished in the basal
part of the main petiole, in which alone it resided in C. montana;
whilst it has increased in the abruptly bent terminal portion.
Clematis flammula.--The rather thick, straight, and stiff shoots,
whilst growing vigorously in the spring, make small oval revolutions,
following the sun in their course. Four were made at an average rate
of 3 hrs. 45 m. The longer axis of the oval, described by the
extreme tip, was directed at right angles to the line joining the
opposite leaves; its length was in one case only 1.375, and in
another case 1.75 inch; so that the young leaves were moved a very
short distance. The shoots of the same plant observed in midsummer,
when growing not so quickly, did not revolve at all. I cut down
another plant in the early summer, so that by August 1st it had
formed new and moderately vigorous shoots; these, when observed under
a bell-glass, were on some days quite stationary, and on other days
moved to and fro only about the eighth of an inch.
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