86, and that of the nine self-fertilised
plants 35.88, or as 100 to 90. The plants in these two latter pots (9
and 10), after being measured, were cut down close to the ground and
weighed: the nine crossed plants weighed 57.66 ounces, and the nine
self-fertilised plants 45.25 ounces, or as 100 to 78. On the whole we
may conclude, especially from the evidence of weight, that seedlings
from a cross between flowers on the same plant have a decided, though
not great, advantage over those from flowers fertilised with their own
pollen, more especially in the case of the plants subjected to severe
mutual competition. But the advantage is much less than that exhibited
by the crossed offspring of distinct plants, for these exceeded the
self-fertilised plants in height as 100 to 70, and in the number of
flower-stems as 100 to 48. Digitalis thus differs from Ipomoea, and
almost certainly from Mimulus, as with these two species a cross between
flowers on the same plant did no good.
CALCEOLARIA.
A BUSHY GREENHOUSE VARIETY, WITH YELLOW FLOWERS BLOTCHED WITH PURPLE.
The flowers in this genus are constructed so as to favour or almost
ensure cross-fertilisation (3/6. Hildebrand as quoted by H. Muller 'Die
Befruchtung der Blumen' 1873 page 277.); and Mr. Anderson remarks that
extreme care is necessary to exclude insects in order to preserve any
kind true. (3/7. 'Gardeners' Chronicle' 1853 page 534.
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