It deserves notice, as bearing
on the nature of Lagerstroemia, that in Lythrum hyssopifolia, which is a
homostyled species, some of the shorter stamens vary in being either present or
absent; and that these same stamens are altogether absent in L. thymifolia. In
another genus of the Lythraceae, namely Cuphea, three species raised by me from
seed certainly were homostyled; nevertheless their stamens consisted of two
sets, differing in length and in the colour and thickness of their filaments,
but not in the size or colour of their pollen-grains; so that they thus far
resembled the stamens of Lagerstroemia. I found that Cuphea purpurea was highly
fertile with its own pollen when artificially aided, but sterile when insects
were excluded. (4/11. Mr. Spence informs me that in several species of the genus
Mollia (Tiliaceae) which he collected in South America, the stamens of the five
outer cohorts have purplish filaments and green pollen, whilst the stamens of
the five inner cohorts have yellow pollen. He therefore suspected that these
species might prove to be heterostyled and trimorphic: but he did not notice the
length of the pistils. In the allied Luhea the outer purplish stamens are
destitute of anthers. I procured some specimens of Mollia lepidota and speciosa
from Kew, but could not make out that their pistils differed in length in
different plants; and in all those which I examined the stigma stood close
beneath the uppermost anthers.
Pages:
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235