123 
CONTRIBUTIONS TO BOTANY. 
against this conclusion. Notwithstanding the anomaly of some 
of its features, the weight of the evidenee here colleeted together 
will, I think, show its close proximity to the Aquifoliacece. The 
distinguished botanist just mentioned, when he described its 
flowers as being dioecious, had only seen the male plant ; they 
are, however, properly speaking, polygamo-dioecious : that is to 
say, in the male flowers the ovary, though present, is rudimentary 
and sterile ; and in the female flower, although the stamens of 
the usual size exist, the anther-eells are abortive and deficient of 
pollen : the two sexes are always in distinct plants, and in all 
these respects the genus resembles Prinos and Nemopanthes ; 
so far, therefore, jPlxtoxicum is quite reconcileable with the 
Aquifoliacece. Its only known species is a native of the eentral 
and southern provinces of Chile, where it forms an evergreen 
tree of some height, with oblong alternate leaves, eovered with 
lepidote scales. Its flowers are small, in simple axillary raeemes 
raueh shorter than the leaves, the whole inflorescence being 
densely covered with lepidote scales similar to those of the leaves. 
Each flower, while in bud, is closely invested by a membrana- 
ceous entire spherical bract, which bursts by laceration from the 
base, and falls off to allow of the expansion of the floral parts : 
we find no other genus in the family possessed of this character. 
The calyx consists of five (rarely six) orbicular concave membra- 
naceous sepals, which are much imbricated in aestivation, and 
are formed of close rows of longitudinal cells, all radiating to- 
wards the circumference from the point of attachment ; and they 
therefore easily split in that direction. The petals, always equal 
in number to the sepals, are alternate with them ; they are longer, 
obovate, narrowed towards the base, with an internal raised keel 
and undulating crispate margins; in the female plant they are 
quincuncially imbricated in aestivation ; in the male flower the 
three internal petals have their apices much inflected and pli- 
cated together, — in all which respects they closely resemble those 
of Villaresia. The stamens, in both sexes, usually five (rarely six), 
alternate with the petals and with as many fleshy glandular pro- 
cesses, all being hypogynous around the ovary. Whenever the 
flower is abnormally 6-merous, the sixth sepal, petal, stamen, and 
gland are always smaller, sometimes almost rudimentary ; and in 
all cases these are forced out of the concentiflc serial lines by crowd- 
ing, so that the perfect , symmetry of the parts becomes thus 
somewhat deranged, showing the normal sti’ucture to be 5-me- 
rous, and that it only becomes 6-merous by a kind of monstrous 
growth. In order to ascertain the nature of the glandular pro- 
cesses, it is necessary to particularize their structure. They are 
described by Sir Wm. Hooker as a nectary, — a term too ambi- 
guous in its meaning ; they appear to me sterile stamens, or 
