M. Vaucher on th^ Char ague of the Lake of Geneva. 245 
in company with M. de Candolle, to see the commencement of 
germination in some of them, which at once decided their na- 
ture. He afterwards collected many other seeds from a marshy 
situation, in which they had been naturally sown in the preced- 
ing autumn, and caused them to germinate in the manner the 
former had done. At a period somewhat later, he also procur- 
ed a great quantity of the young plants, which were easily de- 
tached from the mud in which they naturally grew, together 
with their seeds, rootlets and stems. From observations of this 
kind, he at length succeeded in rendering the history of their 
fructification nearly complete, and has given a description of the 
organs by which it is effected. 
The plant grows in spring, from seeds shed in the preceding 
autumn; and about the beginning of June the rudiments of its 
flowers begin to show themselves at the place of the third or 
fourth whorl or verticil. The flower is composed of a globular 
stamen, which is sessile, of a fine cinnabar colour, and surround- 
ed by a transparent membrane. Immediately above this mem- 
brane, the female flower is placed. It consists of a cylindrical 
capsule, of an elongated form, obliquely striated, and enveloped 
in a semi-transparent membrane, crowned by five or six protSn- 
gations, which Vaucher regards as stigmata. This corpuscle 
swells as it approaches maturity, and becomes ovoidal ; the 
stigmata separate in the form of. a disc with five deep lobes ; 
the exterior membrane hardens and turns white, and the seed at 
length falls. 
In the construction of the germ, we recognise an exterior en- 
velope, formed of a mucilage, at first greenish, afterwards yel- 
low, and, lastly, at the period of maturity, of a dirty-white hue. 
Underneath this mucilage is a second envelope, semitransparent, 
and of a horny consistence ; it forms the only covering of the 
seed, and opens to give birth to the young plant at the period of 
its developement. The interior of the germ is filled with a mu- 
cilaginous or resinous matter, the particles of which are globu- 
lar. These globules have been regarded as the true seminal 
particles ; but they are only particles formed from a liquid sub- 
stance, insoluble in water, with which it presents phenomena re- 
sembling those of oily mixtures. 
VOL. VII. NO. 14 , OCT. 18S2. B 
