Vesicles of the Utricularie. 391 
by Schacht as foliaceous branchlets, which, when young, are 
rolled in, like a crozier, towards their apex, like the fronds of 
ferns; below this apex new leaves are successively formed, at 
the axils of which a little conical body is soon seen to make its 
appearance, composed of small cells, like the commencement of 
abud. This little body soon presents, towards its rounded ex- 
tremity, a small excavation produced by an arrest of development 
of the cells of the apex; the edge thus formed rises more and 
more, and the little cellular body, which was at first sessile, 
soon afterwards shows at its base a prolongation in the form of 
a pedicel. 
The side walls of the young utricle become more and more 
developed, the aériferous cavity which they enclose becomes 
constantly larger, the edges of the side walls become inclined 
towards each other and fold inwards, and the cavity, which was 
originally open, is closed. The old aperture, indeed, presents a 
valve formed by a fold of the margin of the opening. The 
beard which, according to Schleiden, closes this aperture is 
formed subsequently, upon its outer surface. 
After this description of the formation of the utricles, accom- 
panied by the beautiful figures to which one is accustomed in 
Schacht’s works, this author mentions the changes of colour 
which ‘are observed in these organs—a fact previously observed 
by Géppert. He likewise describes the singular hairs which 
oceur on the inner utricular surface. These hairs consist of five 
cells, of which one forms the base, two spread out almost hori- 
zontally, whilst the other two project into the interior of the 
utricle. The basal cell of these hairs, as well as those which it 
supports, results from the division of a small cell, which, in the 
youth of the utricle, makes its appearance like a little stopper 
in the intercellular canals. 
From what precedes, Schacht concludes that the utricles of 
Utricularia are a modification of the ramifications of the axis, 
and not of the leaves. | 
In the month of April 1867, I investigated the formation of 
the utricles in Utricularia minor collected in the marshes of 
Jogny above Vevey. Schacht, who studied the formation of the 
utricles in Utricularia vulgaris, assumes as the rule their forma- 
tion in the axille of the leaves, and deduces therefrom their 
‘ analogy with buds. We see, in fact, little. bodies composed of 
cells make their appearance between the ramifications of the 
leaves; these present a conical form, with their free extremity 
slightly rounded. These little bodies, which are at first com- 
pletely sessile, are soon raised upon a small pedicel, the cells of 
which are afterwards differentiated into an outer layer corre- 
sponding to the layer of parenchyma which follows the veins of 
| O7%* 
