STEMS 



289 



in the ivy, which depends on brick or stone walls for support, the tendril 

 is still further changed to a sucker, or disk. Leaves are often changed 

 to thorns, as in the barberry. 



But it is in the pitcher plants, the sundews, and the "Venus fly 

 traps" that we see the greatest change in leaves. In these plants the 

 leaves are altered so as to form wonderful vessels, or traps, for the 

 capturing of insects. The insects are digested by the plant. Here 

 the order of nature is reversed; for the plant consumes the animal, 

 instead of being consumed by the animal. 



312. Stems. In our study of the bean (cf. 307) we 

 learned that the plumule becomes the leaves of the young 

 seedling. The growth of the plumule also produces a 



FIG. 237. Under this "live oak" Sidney Lanier wrote "Marshes of Glynn." Note the 

 Spanish Moss on the tree. Courtesy of the Field Museum. 



part connecting leaf and root; this is the stem, or stalk. 

 The leaves borne by the stem ordinarily appear only at 

 certain places, called the joints, or nodes. The jointed 

 structure of the stem is readily seen in the bamboo fish- 

 ing pole. The region of the stem just above the place 



