56 



THE LEAF 



iaj. — a, Leaf of an agave, or 

 American aloe, thickened for the 

 storage of water; b and c, cross 

 sections made at points indicated 

 by the dotted lines. 



salad plants of the garden. In some of the fleshy stone- 

 crops and purslanes, the leaves 

 seem to have transformed them- 

 selves into liviilg water bags. 



70. Death Traps. — The sar- 

 racenia, better known as the 

 pitcher plant, or trumpet leaf, 

 is a familiar example of these 

 vegetable insect catchers. Its 

 curious pitcher-shaped, or trum- 

 pet-shaped leaves are traps for 

 the capture of the small game 

 upon which the plant feeds. 

 The lower part of the blade is 

 transformed into a hollow vessel 

 for holding water, and the top 

 is rounded into a broad flap 

 called the lamina. Sometimes 



the lamina stands erect, as in the common yellow trumpets 



of our coast regions, and when this is the case, it is 



brilliantly colored and attracts insects. 



Sometimes, as in the parrot-beaked and the 



spotted trumpet leaf (Fig. io8), it is bent 



over the top of the water vessel like a lid, 



and the back of the leaf, near the foot of 



the lamina, is dotted with transparent specks 



that serve to decoy foolish flies away from 



the true opening and tempt them to wear 



themselves out in futile efforts to escape, 



as we often see them do against a window 



pane. 



If the contents of one of these leaves are 



examined with a lens there will generally los. — Spotted 



be found mixed with the water at the bot- =^rracenia(6>aw- 



olaris) : /, lamina; 



tom, the remains of the bodies of a large j, transparent spots 

 number of insects. Notice that the hairs ^"ft"' '^^'''^)- 

 on the outside all point up, towards the rim of the pitcher, 



