32 BRITISH WILD FLOWERS 



bulbous roots, which are made up of layers of 

 fleshy leaves. If we find a bulbous plant with 

 six petals and stamens, and the veins of the 

 leaves parallel, we may be sure it belongs 

 to this group. Other plants have corms or 

 tubers, as many of the orchids (p. 35), the 

 pig-nut, bulbous crowfoot, arum (Plate IV), and 

 moschatel. Some of the umbels and crucifcrs 

 lay up much material in their roots, and by 

 encouraging this habit we get our garden carrot 

 and parsnip, radish and turnip. So starch is 

 obtained from the arum (176) and potato, which 

 is represented in our flora by the bittersweet (68). 



9. Aroma tics and Poisons 



Some plants are harmless, others useful, and 

 others poisonous. It is well to remember a few 

 general facts. Nearly all the crucifers (Group x) 

 are safe, and, if boiled, may be eaten as vege- 

 tables, even when found in a wild state. Culti- 

 vated, they yield cress and mustard, cabbage 

 and cauliflower, radish and turnip, horse-radish 

 and watercress. Most of the labiates (Group iv) 

 are aromatic, and from them we obtain mint 

 and thyme, sage, pennyroyal, and balm. The 

 umbels (Group vi) are also inclined to be 

 aromatic, but are often very poisonous. The 

 order contains the deadly hemlock, but under 

 cultivation we get from it celery, carrots and 

 parsnips, fennel and samphire, as well as caraway 



