( 414 ) 
is enclosed by the calyx which keeps pace with its growth and one 
can then observe that during the ripening of the fruit the space 
between the calyx-wall and the ovary is filled with a layer of very 
sticky mucilage, derived from the glandular hairs, which during 
this stage are fully active. 
As regards the water, which is found in the female bud and in 
the open flower, I feel justified in assuming that this is secreted by 
the other, pointed hairs of the inner surface of the calyx; I feel the 
more ready to assume this, because in Melandrium rubrum there are 
only found on the inside of the calyx the mucilage-secreting hairs 
and not the pointed ones. Now in the female flowers of the latter 
species the inside of the calyx is also covered at all stages of develop¬ 
ment with a large number of glandular hairs, which evidently already 
secrete mucilage in the young buds; the fruits are also surrounded 
by a layer of mucilage, but no water is secreted in the flowers 
during the flowering period, presumably owing to the above mentioned 
absence of the pointed hairs * 1 ). 
I now wish to show by means of two examples, that the secretion 
of water in the flower is not dependent on the outer or inner sur¬ 
face of the calyx, nor on the outside of the corolla (Datura), but 
that it can also occur on the stamens. 2 ) 
h It is possible that water is also secreted in the female flower of Silene Otites 
Sm. With regard to this plant Schultz mentions, that in Germany the nectar- 
secretion of the female flower is almost always absent, and that of the male flower 
very often, but that in the Tyrol the male (and the hermaphrodite) flowers, like 
the female ones, secrete honey at the outside of the ring which unites the bases 
of the stamens. 
According to Schultz insects can easely reach the honey of the male flower on 
account of its small depth and fairly wide mouth, but in the female flower this 
is probably always quite impossible, because the calyx and the petals are closely 
applied to the ovary. 
1 shook 50 male and as many female flowers of this plant with distilled water 
and tested the water for glucose. I found that the male flowers are abundantly 
provided with nectar, but that the water from the female flowers had not taken 
up a trace of glucose. 
I did not succeed in observing drops of fluid in the female flower and canno 
say whether water is secreted here as in Melandrium album. It seems to me 
most probable that we are here dealing with a flower which is wholly devoid o 
nectar and of water; this is the more likely because the trichomes on the insi e 
of the calyx, which might possibly secrete water, do not occur in Silene Ot & 
2 ) With regard to the occurrence of “Trichomzolten” on the surface of the 
ovary e.g. in species of Lysimachia, in Ononis spinosa and in Verbascum Bn 
taria I must refer for the sake of brevity to my previous communication. Pro 
dings of the meeting of Nov. 28, 1908. 
