( 448 ) 
young calyx (the development of which in all these plants is burried 
on, before that of the other parts of the flower) is protected against 
the dangers of exposure to the atmosphere ; sometimes the calyx is 
protected ‘by glands, which may or may not be active, sometimes 
by a thick covering of hairs, which retains air, sometimes by both 
these means. It is intelligible, that this young organ, the vascular 
bundles of which are as yet unperfectly developed and therefore 
unable to compensate adequately for the loss of water through tran- 
spiration, should require a special, temporary protection, in so far as 
it is not surrounded by bracts. 
Now we see at a later stage, in which the calyx has already 
acquired certain dimensions and in which its anatomical structure is 
nearing completion, that the same glands appear on the inner surface, 
and by their activity more or less fill the cavity of the calyx with 
water; this secretion of water supplements the protective function of 
the calyx towards the other parts of the flower, which are now 
beginning their development. 
Later, in older buds, when the stamens and ovaries have already 
made considerable progress, the same glands appear on the outer- 
and on the inner surface of the corolla. The former, the outer glands, 
are especially active in protecting the petals against excessive trans- 
piration in the short period, between the bursting open of the calyx 
and the development of the petals to their full size — temporarily 
therefore ©. The significance of the hairs on the ner surface would then 
be, that in the same period they keep the sexual organs in a moist space. 
When we see therefore, that the flower is carefully protected against 
transpiration from the first stages of its development to the moment 
of opening, the question naturally arises, whether at the opening and 
during the flowering-period, the sexual organs are under such especially 
favourable conditions, that they require no protection ? 
This is certainly not the case; during the flowering period the 
ovary is not placed in favourable conditions. 
When opening, the flower enters upon a period, in which the stamens 
and the ovaries — exceptions apart — have reached their highest stage 
of development, do not require food for further growth and are in a state 
of rest; the ovaries are awaiting fertilisation in order to be called 
to new life by that stimulus; the stamens in a state of maturity, 
await the evaporation of the superfluous water from the anthers. 
1) This opinion will later be supported by examples; I propose to show, that 
at this stage, when the corolla is still completely closed, water or nectar is found 
in many flowers. 
