Class XIX. Order L 187 



a small neck, its scales tipt with sharp, ascending spines, and 

 connected with a downy web. Receptacle hairy. Seed down 

 feathery. Flowers from June to September. Biennial. 



224. ONOPORDON. 

 ONOPORDOH ACANTHIUM. L. Cotton Thistle. 



Calyx scales spreading every way, awl shap- 

 ed ; leaves ovate-oblong, sinuated, woolly on both 

 sides. 



Frequent in waste grounds, and readily distinguished from 

 the other thistles by its white appearance and the large size of 

 its leaves. Stem erect, tall, winged by the decurrent base of 

 the leaves. Leaves oblong, broad, sinuated, toothed, and spi- 

 nous, covered on both sides with a loose, white, cottony sub- 

 stance. Flowers purple. Calyx globose, wider than it is long, 

 with lanceolate, spreading, cottony, spinous scales. Recepta- 

 cle cellular, like a honey comb. Down rough, short. The 

 Cotton thistle was probably introduced from Europe. It flow- 

 ers in July and August. 



225. VERNONIA. 

 VERNONIA NOVEBORACENSIS. TPilld. Vernonia. 



Leaves lanceolate, rough, serrulate ; corymb 

 fastigiate ; scales of the calyx filiform at top. 

 Willd. 



Syn. SERRATULA NOVEBORACENSIS. L. 



A tall plant, bearing a multitude of dark purple flowers, 

 which turn nearly black in decay. Stem about four feet high, 

 furrowed, purplish, branching at top. Leaves peduncled, lan- 

 ceolate, finely serrate, acuminate, paler underneath. Flowers 

 terminating the stem and branches, in a compound, flat topped 

 corymb. Scales of the calyx ending in a fine slender awn. 

 ^ (ci ^ ount * ' m m i st situations. September. Perennial. 



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