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 Robertianum, 

 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 



