162 
CONTRIBUTIONS TO BOTANY. 
family serves to throw much light on this point. It is shown in 
pi. 6. fig. 14 that Welwitschia (besides its floral envelopes) pre- 
sents a monadelphous ring of regularly formed stamens sur- 
rounding an ovary constituted in the usual manner of angio- 
spermous plants — that is to say, with a simple style and stigma 
surmounting an oblong 1 -celled carpel containing a single erect 
ovule, thus exhibiting a floral development and pointing to a 
position in the system far higher than the gymnospermous 
orders of Coniferce and Cycadacece. But the ovule of the herma- 
phrodite flower is always sterile, and it is only in such flowers 
as are deficient of corolla and stamens that embryo-sacs are 
formed in the ovule which admit of its fertilization ; and hei’e it 
is seen that the style becomes so far depressed that the stigma 
remains sessile on the summit of the carpel, leaving the small 
apical pervious aperture constantly found in the fruits of Wel- 
witschia and its congeners. This depression of a pervious stigma 
I have shown to exist in several other instances. The entire 
development imparts a truly angiospermous eharacter to the 
Gnctacece, notwithstanding the pervious aperture in the carpel, 
while the peculiar mode of fertilization, as Dr. Hooker seems to 
indicate, is analogous to some instances in Sanialacew and Lo- 
ranthacea. I long ago pointed out the existence of vascular 
threads in the viscous cap which crowns the seed in Loranthus 
[Struthanthus) , the nature of which I did not then understand, 
but which may perhaps be analogous to the development shown 
in Welwitschia. 
The involucels in Ephedra, even in a young state, resemble 
those of Welwitschia in this particular — that the margins are 
simply reticulated and petaloid, while the central discoid portion 
is formed of three easily separable laminee, the external plates 
being simply reticulated and epidermoid, while the inner lamina 
consists of numerous closely disposed spicular fibres shaped 
like those shown in Welwitschia ; these are imbedded in paren- 
chyma, as well as two conspicuous distant and parallel nervures 
which consist of bundles of ordinary spiral vessels. 
The bilabiate perigonium in Ephedra is quite reticulated and 
petaloid, and exhibits no trace of any similar fibres or vessels. 
Its achenium bears all the usual features resulting from the 
growth of a regular carpel : it is thick and coriaceous, containing 
within its somewhat fleshy mesoderm a number of long hair-like 
threads of pellucid woody fibres, nearly of its entire length •, 
there is no resemblance in this structure to the perianth of the 
male flowers. Dr. Hooker, however, eonsiders the similar peri- 
carp of Welwitschia to be the growth of a perianth surroundin 
a gymnospermous ovule deficient of any true carpellary coverin 
— a conclusion apparently formed upon hypothetical grounds. 
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