STNGENESIA. srPERFtUA. 17% 



578. ACMELLA. Richard, 



Calix simple, leaflets few. Receptacle oblongs 

 paleaceous; Seeds 4-sided, truncate at tlie sum- 

 mit, naked. 



Herbaceous, stems mosty procumbent, leaves opposite* 

 entire; peduncles solitary, l-flowered, axillary and termi- 

 nal. Flowers yellow. Rays oblong. 



Species. 1. A. repe7is. Spilanthis repens. Mich. 2. occi- 

 dentalis? Hab On the banks of the Missisippi near 

 New Orleans. Obs Stem repent, somewhat pubescent. 

 Leaves ovate, crenate, obsoletely S-nerved, smooth and 

 petiolate; peduncle axillary and grooved, about 3 inches 

 long-; rays 5 to 8?; calix minute. Resembles a small Rtid- 

 beckia. 



A jjenus of 5 or 6 species indigenous to the warmer 

 parts of America, not essentially distinct from Heliopsis 

 either in habit or character. 



579. ANTHEMIS. L. (Mayweed, Chamomile.) 

 Calix hemispherical, subequal. Rays more 



than 5. Receptacle paleaceous; palese ilat, with 

 rigid acuminated points. Pappus none or mar- 

 ginal. 



Herbaceous; leaves mostly multifid; ramuli usually 1- 

 flowered; rays white or yellow, rarely wanting. 



Species. 1. A. nobilis. Common Chamomile. Natural- 

 ized near Lewistown, Delaware. 2. Cotiila. May-weed. 

 Introduced, but now every where a common weed in 

 wastes. 



A genus of about 35 species, almost exclusively indige- 

 nous to Europe. 



580. ACHILLEA. L. (Milltbil.) 



Calix ovate, imbricate. Rays 5 to 10, round- 

 ish. Receptacle paleaceous. Pappus none. 



Herbaceous, seldom suffruticose; leaves multifid or rare-' 

 ly undivided; flowers corymbose; rays white, reddish or 

 yellow. 



Species. 1. A. Millefolium. Naturalized. 2-tometiiosa. 

 Upper Louisiana. Ph. S.asple/dfolia. A variety of ^. JftV- 

 lefolium? 4. Ptannica. SnesijewoTt. From Canada to New 

 York. Ph. 



