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nuine species of Helosis shew on their rhizoma roundish conical buds seated 
on a very short stalk, or altogether sessile, enclosing the rudiments of the fu- 
ture head within a very thin involucre, as a fungus within the volva ; this 
latter after a time splits into 3 or more segments, and emits the flower-head 
enlarged, and furnished with a stalk which is altogether naked except at the 
base, where it is surrounded by the scale-like segments of the withering invo- 
lucre. This is the most simple form of involucre, which in the other genera 
becomes more and more complicated, and finally runs into numerous series of 
imbricated scales which clothe the stipes more or less completely. The more 
important circumstances in the organs of fructification will be found in the cha- 
racters of the orders of Rhizanths. 
In those genera such as Rafliesia, Apodanthus, &c. which grow upon the 
bark of the stems of trees there are some diversities of structure in the organs 
of vegetation that are very remarkable. Blume tells us that Rafflesia Patma 
appears upon the creeping roots or stems of Cissus scariosa in the form of so- 
litary or clustered hemispherical dilations which look like excrescences or ex- 
pansions of the root. These excrescences are something of the nature of 
leaf-buds, consisting of layers of scales and a more solid centre > As the latter 
increase in size they burst through the wrapper by tearing it irregularly from 
the apex towards the base, and develope themselves in the form of numerous 
scales, at first flesh-coloured, then brownish, and finally deep purple, which 
surround the flowers. As soon as these parts are exposed, richly nourished 
as they are by the humid air that surrounds them, they grow with such ra- 
pidity that it is reported that Rafflesia, which when full blown, is a yard 
across, and when unexpanded, is as large as a middle-sized cabbage, only 
takes about three months for its complete formation. Briigmansia has a simi- 
lar mode of developement. 
The seeds of Balanophorese have already been noticed, in the words of 
Endlicher. Blume describes those of Brugmansia Zippelii as containing 1° 
a grumous substance which under a powerful microscope exhibits a lax cellu- 
lar tissue, formed of roundish cells, which become angular by mutual pressure, 
and are filled with grumous matter ; among these are dispersed 2° threads or 
tubes, very numerous, very tender, long, entangled without order, usually 
forked, sometimes irregularly branched. Upon these threads Blume makes 
the following remarks : — “The tender tubes, principally visible in the ripe 
spores of Rhizanths, may be considered analogous to those lowest forms of ve- 
getation which belong to the genus My coderma Pers. of the family Hydi'onematem 
Carus. The parietes of the fruit of Brugmansia are seldom covered with spores 
when the pericarp is closed up, but they constantly are when the plant is decay- 
ing, a circumstance which is attributable to the facility with which the spores 
separate from their stalks, and to the cellulo-gelatinous matter in which the 
fruit' abounds. It is worthy of remark, however, that the spores are attached 
in the same manner as the seeds of more perfect plants, although they are al- 
together different from them in structure. They are, indeed, to be compared 
only to the unfecundated ovules of Phaenogamous plants, which in the latter 
are more completely evolved after impregnation, but in Rhizanths, as in 
other Cryptogamous plants, only after germination. That the ovules of Rhi- 
zanths, while inclosed in the pericarp of their mother ever arrive at the deve- 
lopement of an embryo, seems to be altogether untrue. For I have over and 
over again examined numerous specimens at different stages of formation ; the 
observations have been repeated under the eyes of Reinwardt, and the bro- 
thers Nees von Esenbeck ; as also by Meyer, so celebrated as an anatomist, 
upon specimens preserved in spirits of wine, so that I can deny the possibility 
of any error. How, indeed, can we suppose Rhizanths to be plants furnished 
with an embryo, when they exhibit only the simplest form of cellular organi- 
zation in all their parts. FI. Javcc Rhizanthefe, p.' 23. 
