150 BRITISH PLANTS 



3. Storage of Food in Subterranean Organs — (a) Tubers. 



— (i.) Stem-tubers — e.g., potato, Jerusalem artichoke. 



(ii.) Eoot-tubers — e.g., sweet potato. 



(6) Rhizomes — e.g., ginger, arrowroot. 



(c) Fleshy Roots.— (i.) Of biennials — e.g., carrot, tur- 

 nip, parsnip, swede, mangold, radish, beet. 



(ii.) Of perennials^ — e.g., Manihot utilissima, the man- 

 dioc, from which tapioca is obtained. 



{d) Bulbs — e.g., onion — the leaves of which are full of 

 sugar. 



4. Edible Aerial Organs, yielding most of our table 

 vegetables. 



{a) Stems. — (i.) Sugary pith — e.g., sugar-cane. Maple- 

 sugar is obtained by boring holes in the stem of the sugar- 

 maple, a native of North America, when the sap is setting 

 towards the opening buds in spring. 



(ii.) Starchy pith — e.g., the sago-pahns — from which 

 sago is obtained. 



(6) Leaves — e.g., cabbage, lettuce, spinach. 



(c) Buds — e.g., brussels - sprouts, from a variety of 

 cabbage. 



{d) Young Shoots — e.g., asparagus. 



(e) Petioles — e.g., celery, rhubarb. 



(/) Inflorescences — e.g., cauliflower, broccoli, artichoke. 



5. Seedlings — e.g., mustard and cress. 

 Fodder-Plants. — Animals, in the main, eat the same 



vegetable food as man. Most of our domestic animals 

 are vegetable feeders, and in these the digestive organs 

 are adapted to the consumption of large quantities of 

 raw vegetation. The chief fodder-plants are grasses, 

 leguminous herbs, and root-crops. Other important 

 feeding-stuffs for livestock include oats, maize, beans, 

 bran, etc. (from the milling of wheat), and oil-cake (the 

 residue left after the oil has been pressed out of oil-seeds). 



Accessory Food-Products. — We eat and drink many sub- 

 stances derived from plants which are not strictly food at 

 aU. They are either consumed as aids to digestion, or, 

 because of their stimulating properties, they are employed 

 in the preparation of beverages. Others act medicinally 

 as drugs. 



(a) Spices and Condiments.— These have little or no 

 actual food-value. They serve merely to stimulate 

 appetite or to render food more pleasing. The principles 



