728 REPORT OF NEW JERSEY STATE MUSEUM. 



d. Involucral bracts with hooked bristles, a large course branch- 

 ing plant with purplish flower heads. [Arctium minusY 

 dd. No hooked bristles to the involucral bracts. 



e. Foliage very bristly. Carduus, p. 778 



ee. Foliage not bristly. 



f. Leaves verticillate, flowers pink. 



g. Leaves linear, plant 3-6 dm. high, flower head single, 



10 mm. wide. Sclerolepis, p. 731 



gg. Leaves ovate lanceolate, plant .5-3 m. high, flower 



heads very numerous in a terminal cymous panicle. 



Bupatorium, p. 732 

 ff. Leaves not verticillate. 



g. Flower heads red-purple in a terminal cymcse, 

 panicle. Plant 9-27 dm. high, not aromatic. 



Vernonia, p. 730 

 gg. Flower heads pink, broad in a terminal corymbose 

 cyme. Plant 4-9 dm. high, aromatic. 

 h. Leaves sessile cordate or clasping at base. 



Pluchea foetida, p. 765 

 hh. Leaves petioled. P. camphorata, p. 765 



ggg. Flower heads red-purple in a long, usually dense, 

 terminal spike or spike-like raceme, leaves linear 

 or linear lahc.eolate. Plant 3-20 dm. high. 

 h. Bracts of the cylindrical involucre oblong or 

 oval obtuse, achenes pubescent or smoothish. 

 Lacinaria spicata, p. 740 

 hh. Bracts of the obovoid involucre oblong, obtuse 

 or pointed, achenes hairy. - 



L. graminifoUa pilosa, p. 740 

 gggg. Flower heads blue. Bupatorium, p. 732 



SSSSS- Flower heads purplish, leaves whitish wooly. 



Gnaphalium purpureum, p. 768 

 aa. Ray flowers present around the central disc. * 



b. Rays yellow. 



c. Notched at the end. • Helenium, p. 774 



cc. Rays not notched. 

 d. No pappus. 



e. Achenes with barbed awns. Bidens, p. 772 



ee. Achenes without awns. 

 /. Plant rough. 



g. Leaves 3-7 pointed or lobed. 



Rubeckia laciniata, p. 769 

 gg. Leaves not lobed. 



h. Disc greenish or yellowish. Helianthus, p. 769 

 hh. Disc brown. 



i. Flower less than 100 mm. broad. 

 /. Leaves linear sessile. 



Helianthus angustif alius, p. 769 

 jj. Leaves lanceolate. [Rubeckia hirta]' 



' Burdock, a Weed in waste ground. 



' Black-eyed Susan, a common weed in fields. 



