NUTRITION 
387 
tive translucent spots away from the concealed opening, one or all, which 
prevent the escape of insects that wander in and sooner or later drown 
in the fluid; whence nitrogenous compounds derived from their bodies 
by decay or digestion enter the 
tissues of the pitcher. 
Flytrap. Venus 's flytrap 
(Dionaea, fig. 657) has leaves 
with two terminal lobes about 
i cm. long, hinged about the 
midrib, and fringed with long 
slender teeth, which interlock 
when the lobes shut together (figs. 
658, 659) . On the surface of each 
lobe are three large sensitive bris- 
tles, and if one of these be bent so 
as to compress the basal cell, the 
lobes shut like the two jaws of a 
trap. Insects, flying or crawling, 
which come into contact with the 
bristles are often caught. Then 
the glands upon the upper (in- 
ner) surface pour out a digestive 
fluid, the proteins are reduced 
to such simplicity that they can 
enter the tissues, and after a few 
days the leaf opens again. Its 
water mate, Aldrovanda, has a WISSSilK^ 
similar but smaller trap, by which 
minute swimming crustaceans, J^gjjp' ? 
Daphnia, Cyclops, etc., are often FIGS. 658, 659. Cross sections of the termi- 
rjuiaht na ' ^^ ies f rrmn g the "trap" of Dionaea: 
' 658, enlarged view, closed position, diagram- 
Sundew. Drosera, the sun- matic; , digestive glands; , p.parenchymatous 
HPW ha itc Ipavpc ffio- ftSr^ tissues whose varying turgor opens and closes 
1CW > naS )8 5) the "trap"; 5, sensitive bristles; 659, outline, 
fringed and covered above with on a smaller scale, of same in an open position. 
stalked glands that secrete a ~ AfterKNY - 
viscid transparent fluid, in which small insects alighting may become 
enveloped by their own struggles, and further (in our species) on account 
of the inflection of the stalks of the glands. When an insect is caught, 
the character of the secretion changes; it becomes more watery and 
