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consists of thin-walled cells, which leave large intercellular spaces 
between them. The vascular bundles are strongly developed and 
take up almost the whole thickness of the leaf. In no part of the 
transverse section can starch be detected, but the whole of the 
mesophyll is very rich in glucose; starch occurs only in the nectary. 
In a section through the nectary, 4 different parts can be made out 
even at low magnification. First there is the honey-secreting tissue 
proper, consisting of 3—4 layers of small clost-fitting cells, densely 
filled with protoplasm and containing large nuclei. Under this there 
is a tissue, 8 or more cell-layers thick, composed of larger cells 
with very distinct intercellular spaces; these cells are crowded with 
numerous small starch-grains. Outwards or downwards there follows 
the region of the vascular bundles, where the mesophyll still contains 
starch. Finally the latter tissue gradually passes into that containing 
chromatophores, which again consists of considerably smaller cells 
and is closed off on the outside by an epidermis, consisting of pina- 
coid cells, the outer wall of which, in this region, is much thicker 
than in any other part of the perianth. 
The starch which collects under the secretory layer, is already 
found in sections of very young nectaries, for instance in buds 
about 2.5 em. long. 
That it’ is from this material that nectar is afterwards formed, 
becomes evident on the examination of nectaries, which have already 
been forming honey-drops for some days; a distinct diminution of 
starch may then be observed, and at the end of the flowering no 
starch whatsoever is found. 
A section through a stamen shows, that the latter is traversed by 
a comparatively thin vascular bundle, and that for the rest the tissue 
consists of large cells, which give a very strong reaction with 
Frurine’s test-solution for glucose. Externally the tissue is enclosed 
by a small-celled epidermis with a comparatively thick outer wall, 
which presents a granular cuticle. It may be, that by being enclosed 
by stamens, which are rich in glucose, the ovary is not so completely 
protected against the harmful consequences of exposure to the atmos- 
phere as an inferior ovary is by the thalamus, but nevertheless the 
two kinds of protection are comparable; in any case the ovary thus 
receives considerable protection during development. 
It may be of interest to note, that the stamens continue to enclose 
the ovary, when the anthers have fallen off. The filaments remain 
fresh and in their original position, as long as flowering continues. 
The secretion of nectar begins soon after the perianth-leaves 
separate, and the tips of the anthers protrude out of the flower. 
