THE LEAF 83 
and absorbing water. The bromeliads (plants of the pineapple 
family) furnish excellent examples of absorbing hairs (Fig. 490). 
Carnivorous leaves. ‘There are several 
kinds of leaves which catch insects or other 
small animals. 
The pitcher plants have their leaves modi- 
fied into pitchers in which water collects. 
The best-known pitchers belong to the tem- 
perate zone genus Sarracenia (Fig. 73) and 
the tropical genus Nepenthes (Fig. 74). The 
species of Sarracenia are rosette plants ; that 
is, the leaves arise in a cluster from a very 
short stem. The species 
of Nepenthes are vines 
on which the pitchers 
are borne at the ends 
of long, tendril-like 
leaves. Insects” are 
drowned in the water 
2 in the pitchers. In the 
Fig. 73. Pitcher leaf issih of the Denes 
>», Sarracenia the insects 
(x 4) 
are decomposed by the 
action of bacteria, while the pitchers of the 
genus Nepenthes excrete a digestive fluid. 
After the insects are decomposed, the prod- 
ucts are absorbed by the leaves. The pitch- 
ers of Nepenthes frequently collect so much 
clear water that it can be used by people 
for drinking. In such cases it would seem 
probable that the leaves not only furnish Reape oy oe eae 
the plants with materials from the bodies Nepenthes. (x4) 
of the captured insects but also with water. 
The sundews (Drosera spp.) are small plants which have their 
leaves arranged in the form of a rosette (Fig. 75). These leaves 
are thickly covered with glands which are borne on slender stalks 

of Sarracenia. 

