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OF TENTACLES OF RORIDULA. 89 
palisade and spongy parenchyma, but only elongated chloren- 
chyma cells united together at their extremities and forming 
irregular rows between which are large intercellular spaces. 
Underneath the vascular bundle there are numerous large loose 
cells of irregular outline, and small intercellular spaces. Outside 
this is a crescentic group of pitted sclerenchyma-elements, and 
there is a similar group occurring above the bundle, and sepa- 
rated from the epidermis by a single row of cells. The central 
vascular bundle itself is surrounded by a sheath, one or two cells 
thick on the flanks and on the lower side but much thicker on 
the upper. A gradual passage may be traced between them and 
the sclerenchymatous cells. The xylem is well developed. The 
phloem is divided into two groups, which approach each other 
closely in the middle line though they do not meet. 
The structure of the teeth resembles that of the apex leaf 
(Fig. 22). The vascular bundle runs up the centre as far as the 
pedicel of the terminal tentacle which it enters. In structure it 
resembles that of the mid-rib except that the large loose cells 
are absent. Stomata are fairly numerous, and the epidermis 
bears no chlorophyll. The chlorenchyma consists of elongated 
cells resembling those of the mesophyll of the leaf, and form a 
ring around the vascular bundle. 
STRUCTURE OF TENTACLES OF RORIDULA. 
Although the arrangement of the tentacles is different in the 
two species, their structure is similar, and one description will 
suffice, therefore, for both. 
The glands of Roridula are pedicellate, and vary in size from 
small ones, which require the aid of a lens to be visible, to large 
Ones about 1 cm. in length. 
They all have essentially the same construction, which is 
typically seen in one of the larger glands, namely, a_pluri- 
cellular pedicel bearing at its extremity an ovoid swelling, the 
Stlandular head (Fig. 23). 
THE PEDICEL.—This is usually slightly swollen at its point of 
origin from the epidermis of the leaf, but above the base is of 
uniform thickness. It agrees with the corresponding structure 
in Drosera and Drosophyllum in being pluricellular, but differs 
