342 PLANT-LIFE 



tected by various means. Some are poisonous, and 

 animals seem to avoid them instinctively ; it is not im- 

 probable that certain curious distinctive characters of 

 poisonous plants are warning features — the lurid purple 

 flowers of the aconite (Aconitum napellus) and the 

 dingy-yellow flowers of the Henbane {Hyoscyamus niger, 

 Plate XX.), with their curious purple veining, are ex- 

 amples of what is meant. The adage " What is one's 

 food is another's poison " is illustrated by the Deadly 

 Nightshade {Atropa belladonna) . This plant is poisonous 

 to men and cattle, but the larva of a certain kind of 

 beetle'thrives upon it; probably the toll exacted by the 

 larva is not sufficient to impair the vigour of the plant. 

 It is said that rabbits may eat it without fatal conse- 

 quences. The Poppies and the Foxglove {Digitalis 

 purpurea) are poisonous. 



Other plants, though not actually poisonous, have an 

 objectionable taste, and equally as objectionable an 

 odour. The Herb - Robert {Geranium Rohertianum, 

 Plate LXVI.) and the Woundworts {Stachys, Plate 

 LXIX.) are disagreeable both in taste and smell, the 

 latter being accentuated when the plants are crushed. 

 The Sweet Briar {Rosa rubiginosa) has a scent, due to 

 secretion of an ethereal oil by foliage glands, which is 

 attractive to men and insects, but probably a stench in 

 the nostrils of a grazing beast. 



Many plants which might provide animals with de- 

 lectable food are protected from their incursions by 

 external characters. Leaves may be too tough for 

 ready consumption, or be rendered objectionable by a 

 clothing of hairs. In many species of Mullein {Ver- 

 bascum) the leaves are clothed with branched, radiating 



