COMPOUND FLOWERS 163 



and bears numerous clusters of rather small, deep purple (sometimes 

 white) flowers. The leaves are thickly armed with short thorns, 

 which are often of a brownish hue. Moist meadows and borders 

 of fields ; very common. Fl. July, August. Biennial 



3. C. arvensis (Creeping Plume- thistle). Heads of flowers 

 numerous, stalked ; the scales of the involucre closely pressed, 

 pointed, but scarcely thorny ; stem not winged ; root creeping. 

 A handsome weed, about 2 feet high ; the flowers, which grow in 

 a corymbose manner, are of a light purple colour, and smell like 

 those of the Musk Thistle. The staminate and pistillate flower- 

 heads grow on separate plants, the former being roundish, and the 

 latter egg-shaped. Borders of fields ; very common. Fl. July. 

 Perennial. 



4. C. pralensis (Meadow Plume-thistle). Heads of flowers mostly 

 solitary ; stem-leaves few, soft, wavy. A small plant, 12-18 inches 

 high, with a cottony stem, bearing a few leaves, and rarely more 

 than one small purple flower. Moist meadows ; not general. 

 Fl. July. Perennial. 



5. C. acaidis (Dwarf Plume-thistle). Heads of flowers solitary, 

 and stemless or nearly so. A low plant, consisting of a few thorny 

 leaves, and a single, almost stemless, purple flower, by which cha- 

 racter it is readily distinguished from all the rest of the Thistle 

 Tribe. Dry gravelly or chalky pastures ; not general, but in some 

 places very abundant, and a pernicious weed. Fl. July, August. 

 Perennial. 



Less common species of Cnicus are C. eriphorus (Woolly-headed 

 Plume-Thistle), distinguished by the thick white wool which clothes 

 the scales of the very large flowers ; C. tuberosus (Tuberous Plume- 

 Thistle), which grows only in Wiltshire, an 

 erect single-stemmed plant, with a single 

 large, purple flower; C. heterophyllus (Melan- 

 choly Plume-Thistle), a mountain plant, with 

 an erect, cottony stem, and a single, hand- 

 some, purple flower. 



19. Onopordium (Cotton -thistle) 

 1. 0. Acanthium (Scotch Thistle). The 

 involucre is globose, with the scales spreading 

 in all directions ; the stem is winged, with 

 rough cottony leaves, and attains a height of 

 \-6 feet ; the flowers are large, of a dull purple 

 hue, and mostly solitary, or but slightly clus- 

 tered at the ends of the branches. This 

 species is the true Scotch Thistle, the national 

 emblem. Waste ground and roadsides chiefly Onopordium Acanthus 

 in the south. Fl. July, August. Biennial. ^ Scotch Thistle) 



