When
fully grown the ten tallest plants in each row were selected and
measured to the tips of their highest leaves, as well as to the summits
of their male flowers. The crossed averaged to the tips of their leaves
54 inches in height, and the self-fertilised 44.65, or as 100 to 83; and
to the summits of their male flowers, 53.96 and 43.45 inches; or as 100
to 80.
Phalaris canariensis.
Hildebrand has shown in the paper referred to under the last species,
that this hermaphrodite grass is better adapted for cross-fertilisation
than for self-fertilisation. Several plants were raised in the
greenhouse close together, and their flowers were mutually intercrossed.
Pollen from a single plant growing quite separately was collected and
placed on the stigmas of the same plant. The seeds thus produced were
self-fertilised, for they were fertilised with pollen from the same
plant, but it will have been a mere chance whether with pollen from the
same flowers. Both lots of seeds, after germinating on sand, were
planted in pairs on the opposite sides of four pots, which were kept in
the greenhouse. When the plants were a little over a foot in height they
were measured, and the crossed plants averaged 13.38, and the
self-fertilised 12.29 inches in height; or as 100 to 92.
When in full flower they were again measured to the extremities of their
culms, as shown in Table 6/98.
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