PART III. | THE MECHANISMS OF FLOWERS. 129 
their papillar inner surfaces upwards. The honey is secreted as in 
Dianthus. I omitted to watch the flowers in their season, and can 
only mention Sphinx ligustri, L., as a fertiliser; it visited the 
flowers of this plant in my garden one evening during slight rain, 
and sucked them with the usual rapidity of the hawk-moths. I 
have also found Halictus morio, F. 9 collecting pollen on the 
flowers (July 13, 1869). 
| Silene rupestris, L., is proterandrous, and is visited by numerous 
insects. It fahabits the same localities as Gypsophila repens, 
and secretes and conceals its honey in the same way as that 
species. Its flowers are equally conspicuous, but stand some- 
what isolated on sparingly branched stalks; owing probably to 
this circumstance, the power of self-fertilisation has not been 
entirely lost (609). 
Silene acaulis, L., ascends in the higher Alps to a height of 
over 10,000 feet. Its low tufts closely studded with pink or 
carmine flowers attract so many butterflies that as a rule the plant 
has been able to dispense with the power of self-fertilisation. 
Most tufts are exclusively staminate or pistillate, and only rarely 
hermaphrodite and proterandrous. The latter in case of need fer- 
tilise themselves. I have observed eighteen species of butterflies 
on this flower (609). 
As Silene acaulis is adapted for diurnal Lepidoptera, so S. inflata, 
Sm., and S. nutans, L., are adapted for the nocturnal forms. I 
found both on the Alps, visited in the evening by Noctuide, and 
in the daytime. by bumble-bees. Silene nutans, L., is markedly 
proterandrous. According to Kerner, each flower opens upon 
three successive nights, on which the outer stamens, the inner 
stamens, and the stigmas are exserted respectively. According to 
Ricca (665), the flowers are sometimes diclinous by incomplete 
development of the stamens, that is to say, gynodiecious. Silene 
inflata. L., is tricecious and polygamous, like S. acaulis. 
Lychnis flos-Jovis, L., is distinctly proterandrous; L. rubra, 
Weigel, is tricecious and polygamous. Both have bright red 
flowers, and are greatly frequented by butterflies on the Alps (609). 
 " Lyehnis Viscaria, L., is also adapted for cross-fertilisation by 
butterflies (590, I1.). 
: Lychnis alpina, L.—The proterandrous flowers are figured and 
described by Axell (17). 
57. LYcHNIS FLOS-cucuLI, L.—In regard to the position of 
the honey, the flowers of this plant are intermediate between 
K 
