172 ORDER SUPERFLUA. 



duce no seed. In what, however, are called the 

 quill-flowered varieties the florets are only partially 

 slit open, the remaining part being narrow and tubular. 



In Achillea, or Millfoil, the common species so well 

 known for its compoundly and finely divided leaves, 

 somewhat resembling Tansey, and producing corymbs 

 of white flowers, the calyx is ovate, imbricate and un- 

 equal ; the rays 5 to 10, are roundish, and short. 

 The receptacle chaffy (or leafy), and the seeds without 

 either pappus or border. 



The curious American genus Helenium, of which 

 one tall growing species (H. autumnale) is quite com- 

 mon in wet places, flowering from August to Septem- 

 ber, having decurrent, lanceolate, serrated leaves, and 

 corymbose, showy yellow flowers, is characterized by 

 having a simple, many-parted, spreading calyx. The 

 i ays 3-cleft ; the receptacle naked, globose, bearing 

 chaffy scales near its margin. The seed villous ; and 

 the pappus of 5-awned scales (or chaffy leaflets). 



The African Mary gold, or Tagetes, a Mexican 

 genus, 2 of whose species we have in common cultiva- 

 tion, are curiously distinguished by having a tubular 

 calyx of one piece, 5-toothed at its summit ; and 

 about 5 permanent florets to the ray. The recepta- 

 cle is naked j and the seeds are crowned with about 

 5 unequal chaffy scales. The leaves are very finely 

 subdivided, and the whole plant, at least the common 

 kinds, gives out, on touching, a strong odor, similar to 

 Rue. 



Another very showy ornament to our flower gardens 

 are the species of the genus Zinnia, also originally 

 from Mexico, and chiefly annuals. They have a 

 look of Tagetes, but have an imbricated, round scaled 

 calyx ; and 5, or more, remarkably persisting broad 

 rays. The receptacle is chaffy ; and the pappus con- 

 sists of 2 awns. Besides those, now well known in 



