14 BRUCE—TIHE GLANDS OF BYBLIS GIGANTEA. 
When an insect alights on one of the leaves, it first comes 
in contact with the drops of secretion on the heads of the stalked 
glands (which continually secrete). It is held by the secretion 
of these glands. In its efforts to escape, however, it moves 
across the leaf, and thus comes in contact with the secretion 
from neighbouring glands. It ultimately becomes so surrounded 
by the secretion that it is suffocated, and falls down helpless on 
to the sessile glands below, which after a short time pour forth 
their secretion, and after digestion of the remains, the soluble 
matter is absorbed. 
I saw flies caught by the plant in this way. The secretion 
from the stalked glands is in the form of round drops, which 
are easily removed on touching the gland with a needle, and 
are so viscid that they may < drawn out into thin threads many 
centimeters long. 
The above record of experiments upon the activities of the 
glands of Byéblis gigantea discloses a parallel with the activity 
of the glands of Drosophyllum lusitantcum. In Drosophyllum 
the glands are of two kinds, stalked and sessile ; the sessile 
glands do not secrete unless stimulated, when they pour out their 
digestive secretion and afterwards absorb the digested matter. 
The stalked glands continually secrete, are not digestive, and 
are chiefly useful to the plant for catching insects. But whilst 
there is this functional parallel the construction of the gland is 
different in the two plants. 
It seems to me to be probable that the sessile glands of 
Drosophyllum lusitanicum have been derived from the stalked 
glands by the loss of the pedicel ; while in the case of Bydls 
gigantea, it is possible that the opposite is the case, namely, 
the stalked glands have been derived from the sessile ones, 
since the pedicel is unicellular, and might be considered to have 
arisen by the elongation of the single cell which corresponds 
to it in the sessile glands. 
