224 PRACTICAL LESSONS IN SCIENCE. 



Note the arrangement of the unbranched roots, their wrinkled 

 surface and the root hairs. Make transverse and longitudinal 

 sections of the larger roots, and notice the cortical, parenchyma 

 and fibro-vascular regions, and the thickness and peculiarities of 

 each. In the fibro-vascular region several large tracheary vessels 

 may be seen. 



Notice the size and shapeof the root stalk, the number of nodes 

 and scars of former branches, and the number of roots from each 

 node. Make the two sections and note the vascular bundles amid 

 a mass of white material, which is probably reserved food. Crush 

 a bit of the white matter in a little water and add a drop or two 

 of iodine solution and note change in color indicating starch. 

 Compare the ends of the root stalk, studying especially the grow- 

 ing end as a whole and in longitudinal section, and note the form, 

 structure and veining of the scales or leaves of the root stalk. 



Study the aerial stem with its whorl of leaves and flower, note 

 its form, size and the absence of nodes. Make the two sections 

 and note the three tissue systems, especially the two parts of the 

 vascular area, the light colored or cortical portion toward the out- 

 side, and the darker woody portion toward the center of the stem. 

 Notice the number, shape, arrangement and position of the foliage 

 leaves, especially the outline of the apex and base of each. Note 

 also the petiole and the venation or mode of veining of the leaves, 

 which is not usual in this order. Make a drawing of a leaf. 



The flower is composed of four whorls of organs, the lower, of 

 three greenish sepals, the calyx, the next of three colored petals, 

 the corolla,, the next of six stamens, the andrcecium and the in- 

 nermost, of three partly united pistils, the gyncecium, and all 

 these parts stand on the broadened end of the stem called the re- 

 ceptacle. Note that the parts of a whorl alternate with those of 

 the whorl next to them. Notice the color, shape and venation of 

 both sepals and petals. In studying the anthers, notice the 

 pollen sacs, and the connection between them, which is a continu- 

 ation of the filament. In the filament notice the vascular 

 bundles, and the fundamental tissue. Note also the way the 

 anther opens and the character of the pollen. 



