CLASS XIX. ORDER I. 301 



lar ; down consisting of awns prickly backward ; 

 calyx nearly equal, invested with leaves. 



336. MiKAXiA. Receptacle naked: down simple; 

 calyx four or six leaved, and four or six flowered. 



337. EuPATORiuM. Receptacle naked ; down sim- 

 ple or rough ; calyx imbricate, oblong ; style longer 

 than the corolla, cloven half way down. 



Order 11. SUPERFLUA. Florets of the 

 disc with stamens and pistils, those of the ray with pistils 

 only ; all fertile. 



338. Artemisia. Receptacle mostly naked ; down 

 none ; ray none ; calyx imbricated with roundish con- 

 nivent scales. 



339. Tanacetum. Receptacle naked : down some- 

 what marginate ; florets of the ray obsolete, three 

 cleft : calyx imbricate, hemispherical, with acuminate 

 scales. 



340. CoNYZA. Receptacle naked ; down simple or 

 rough ; calyx imbricate, roundish ; florets of the mar- 

 gin three cleft. 



341. Gnaphalium. Receptacle naked : down feath- 

 ery or rough; calyx with scarious, colored scales; 

 florets of the margin subulate. 



D. Flowers radiate. 



342. Chrysanthemum, Receptacle naked ; down 

 none ; calyx hemispherical, imbricate, with the scales 

 dilated, and membranous at the margin. 



343. Inula. Receptacle naked ; down simple; ca- 

 lyx imbricate; rays numerous; anthers with two 

 bristles at base. 



344. Erigeron. Receptacle naked; down simple; 



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