trous to an extreme degree and yet
retain their full fertility. Gallesio, who certainly had great
experience,[408] often attributes sterility to this cause; but it may
be suspected that in some of his cases sterility was the cause, and not
the result, of the monstrous growths. The curious St. Valery apple,
although it bears fruit, rarely produces seed. The wonderfully
anomalous flowers of _Begonia frigida_, formerly described, though they
appear fit for fructification, are sterile.[409] Species of Primulae,
in which the calyx is brightly coloured, are said[410] to be often
sterile, though I have known them to be fertile. On the other hand,
Verlot gives several cases of proliferous flowers which can be
propagated by seed. This was the case with a poppy, which had become
monopetalous by the union of its petals.[411] Another extraordinary
poppy, with the stamens replaced by numerous small supplementary
capsules, likewise reproduces itself by seed. This has also occurred
with a plant of _Saxifraga geum_, in which a series of adventitious
carpels, bearing ovules on their margins, had been developed between
the stamens and the normal carpels.[412] Lastly, with respect to
peloric flowers, which depart wonderfully from the natural
structure,--those of _Linaria vulgaris_ seem generally to be more or
less sterile, whilst those before described of _Antirrhinum majus_,
when artificially fertilised with their own pollen, are perfectly {167}
fertile, though sterile when left to themselves, for bees are unable to
crawl into the narrow tubular flower. The peloric flowers of _Corydalis
solida_, according to Godron,[413] are barren; whilst those of Gloxinia
are well known to yield plenty of seed. In our greenhouse Pelargoniums,
the central flower of the truss is often peloric, and Mr. Masters
informs me that he tried in vain during several years to get seed from
these flowers. I likewise made many vain attempts, but sometimes
succeeded in fertilising them with pollen from a normal flower of
another variety; and conversely I several times fertilised ordinary
flowers with peloric pollen. Only once I succeeded in raising a plant
from a peloric flower fertilised by pollen from a peloric flower borne
by another variety; but the plant, it may be added, presented nothing
particular in its structure. Hence we may c