in ANATOMY STUDY OF THE SHOOT 19 



EXPT. 10. Cut sections through the apex of the buds of the Horse 

 Chestnut and Sycamore. Note 



(i) The overlapping scale leaves. 



(ii) The young foliage leaves. 



(iii) The apical growing point. 



(iv) The arrangement of the different parts should be shown in a 

 sketch. 



Kinds of Plants. Plants may be annual, biennial, or 

 perennial, i.e., they may last one, two, or more years. 



Annual Plants produce seeds during the first year of growth 

 and then die. Wheat, Barley, Peas, Beans and Mignonette, are 

 examples. 



Biennial Plants are those which during the first year of 

 growth store up reserve materials, these substances being used 

 for the production of flowers and seeds in the second season. 

 Thus, biennial plants must live two years. Turnip, Cabbage, 

 Foxglove, and Beet, are typical examples. 



Perennial Plants live and grow for three or more years. 

 They may be trees or shrubs, such as the Oak, Beech, and 

 Hawthorn ; or they may be herbs, like the Daisy, Snowdrop, 

 Wild Hyacinth, and Primrose. The herbaceous perennials 

 have underground stems from which the leaves and flowers are 

 produced ; the aerial parts die down each season. 



The Ascending Axis. The ascending axis is a very 

 important part of the plant ; though leaves may be absent, and 

 in a few cases roots may not be developed, the stem is always 

 present. The stem bears buds, leaves, flowers, and fruits, and 

 connects the leaves with the roots. If the stem is produced by 

 the elongation of the plumule, it is called primary or normal. 

 The place on the stem from which a leaf arises is termed a 

 node, and the space between two nodes is termed an inter- 

 node. In some cases the nodes are thickened, as in the 

 Stitchwort, and in a few cases adventitious roots may spring 

 from them, as in the Ivy. 



Herbaceous Stems. The ascending axis may be soft 

 and green, and die down at the end of the season, when it is 

 called a herbaceous stem. Herbs are plants which fulfil their 

 life-history in a single season ; they are also called annuals. 

 Annuals, such as the Stock, Oats, and Indian Corn, also 

 produce seeds at the end of their period of growth. 



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