six of them were vertically dependent; these therefore had travelled
through 180o in this time. Ten were extended sub-horizontally, and these
had moved through about 90o. Three very young peduncles had as yet moved
only a little downwards, but after an additional 24 h. were greatly
inclined.
At the time when the flower-heads reach the ground, the younger imperfect
flowers in the centre are still pressed closely together, and form a
conical projection; whereas the perfect and imperfect flowers on the
outside are upturned and closely surround the peduncle. They are thus
adapted to offer as little resistance, as the case admits of, in
penetrating the ground, though the diameter of the flower-head is still
considerable. The means by which this penetration is effected will
presently be described. The flower-heads are able to bury themselves in
common garden mould, and easily in sand or in fine sifted cinders packed
rather closely. The depth to which they penetrated, measured from the
surface to the base of the head, was between 1/4 and ? inch, but in one
case rather above 0.
Pages:
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853