MODIFICATIONS OF ORGANS. 107 
surface is covered with secreting glands, as in Drosera, and 
which possess similar digestive powers. 
Fig. 211. Leaves of Dionwa, shut and open, * 
Several other plants have the same properties as Sundews, 
though probably not to the same extent. Thus,-in a few 
swampy districts in different parts of this colony, small semi- 
aquatic plants, called Bladderworts (Utricularia), are to be 
found. In these the submerged branches bear small bladder- 
like structures, which are evidently . 
—to judge from their position— 
modified leaves. These bladders, 
which are hollow, have an opening 
by means of which small aquatic 
animals can enter; and it is rare 
to find a bladder without one or 
more minute water-fleas or insects 
in it. Sometimes they are quite 
full of animal remains in various 
Stages of decomposition. Appa- 
rently, the want of dissolved oxy- 
gen in the water contained inside 
the bladders proves fatal to the 
animals which enter, for, once they 
are in, they never seem able to get 
out again, but die where they are 
caught. Probably, also, their bodies Fig. bie Bubmersed branch 
decay and furnish a small supply of of Utricularia monanthos 
nitrogenous food to the plant, for (mag.). 
the interior of the bladders is fur- 
nished with peculiar cells standing together in fours en short 
Stalks, and whose function is apparently absorptive. 
aS Car ae eee ee te), NOP Eee ew 
_ The sensitive hairs on the inner faces of the leaf-blade have been 
omitted in the drawing. | 
