COMPOSITE FAMILY 



275 



species, readily distinguished from every other British Thistle by 

 the long inner bracts of the involucre, which are straw-coloured 

 and glossy, and spread in a radiate manner so as to resemble 

 petals. In dry weather they lie flat, but when the atmosphere 

 is moist, they rise and form, as it were, a penthouse over the 

 florets. Their texture is like that of Everlasting Flowers ; hence 

 they scarcely alter their 

 appearance when dead, 

 and, as the whole plant is 

 remarkably durable, they 

 often retain their form and 

 position till the succeeding 

 spring. On the Continent 

 the large white flower-head 

 of one species, C. acaulis, 

 is often nailed upon cottage 

 doors by way of a hygro- 

 meter, as it closes before 

 rain. — Dry heaths. — Fl. 

 June — October. Biennial. 



28. Arctium (Burdock\ 

 — Stout, erect, branching 

 plants, with very large, 

 stalked, cordate leaves; a 

 globose involucre of long, 

 stiff, spreading, spinous, 

 hooked bracts; flat, scaly 

 receptacle; florets a,\\ tubular 

 and perfect ; anthers tailed ; 

 pappus in several rows of 

 short, simple hairs. (Name 

 from the Greek arktos, a 

 bear, from the rough burs.) 



1. A. Lappa (Great Bur- 

 dock). — A large and stout 

 herbaceous plant, remark- 

 able for the picturesque character of its large, wavy leaves, which 

 are often introduced by artists into the foreground of their land- 

 scapes. The petioles are solid ; the flower-heads long-stalked^ in 

 a loose corymb, hemispherical, very large ; involucre glabrous and 

 green, or sometimes interwoven with a white, cottony substance ; 

 florets purplish-red. Waste places ; not uncommon. The hooked 

 spines of the involucre attach the heads when in fruit to the coats 

 T 2 



Arctium minus {Lesser Bnrdook). 



