200 DICOTYLEDONOUS. 



1. I. Frutescens. a shrub with numerous opposite branches, slightly 

 furrowed, soinewhat scabrous <ind pubescent vviien young. Leaves opposite, 

 lanceolate, attenuate at the base, deeply serrate, scabrous, of a greenish hue. 

 Flowers nKiWary, furming terminal panicles. Involufre viscidly pubescent 5- 

 leaved, leavps nearly round. Hay fiorets 5, those of the disk 6-7. 



Pale purple. T^. July— September. On the sea coast. 3-S feet. 



2. I. Imbricata. Stem herbaceous, terete, slighdy angled towards the 

 summit, giaorous, becoming |)urple. 2,eai;es sessile, linear-lanceulaie, cune- 

 ate, succulent, the upper ones usually alternate and entire, the lower Irequent- 

 ly opposite a, id toothed. Fcowers axillary, pen lulous. Involucre with 6-9 

 fleshy leaves, with the margins lacerate. Ray tiorets 2, those of the disknu* 

 merous. 



White. %. July— October. On the sea coast. 



Cenus LXVI. ambrosia. 



Flowers numerous, staminate florets, with the involucre 

 hemispherical, 1-leaved, many flowered. Anthers approxi- 

 mate, but not united. Receptacle naked, pi. tiilate florets with 

 the involucre 1-leaved, entire, or 5-toothed, l-flowered. Co- 

 rolla m>ne. Styles 2. i-Vi^iii a nut formed from the indura- 

 ted caly\5 1— jced. d. 



1. A. Trifida. S^em erect, rough, hirsute. Zeaue.s usually opposite, 3-lo- 

 bed, serrate, die lobeii oval lanceolate, acuminate, hairy, serrate. Flowers 

 in small axillary and terminal .'^pikes, forming a large panicle, staminate flo- 

 rets numerous, solitary at the summit of the spike, pistilate ones in small clus- 

 ters at the base. Involucre of the staminate, tiorets 5-8 lobcd, hairy. Corolla 

 tubular. Involucre of the fertile florets persistent, 5-lobed. Fruit with 6 

 spines. Bitter weed. 



White. ©. August — September. Common. 4-6 feet. 



2. A. Elatior. 5'<e/?i virga'e, pubescent when young, ieanes bipinnati- 

 fid, nearly glabrous; peiioles ciliate. Flowers in paniculate racemes, hi- 

 voZacre of the staminate florets, globular, somewhat hairj^ fertile florets in 

 small clusters. Nut with 6 short spines. Hog weid. Roman wormwood. 



White. #. July — September. Middle, upper Car. Ga. 4-8 feet. 



3. A. Artemisifolia. Stem erect, slightly pubescent, fastigiately branch- 

 ed. Z«effves tovvards the base bipinnanfid, opposite, those towards the sum- 

 mit, pinnatifid opposite, nearly glabrous on the upper surface, pubescent be- 

 neath. Racemes terminal by threes. Involucre of the staminate florets, glo- 

 bular ; fertile florets axillary, sessile, spines short. 



White. #. August— September. Mountains. 4-6 feet. 



4. A Paniculata. Stem erect, paniculately branched, villous. Leaves al- 

 ternate towards the base, bipinnatifid towards the summit ; segments all 

 lanceolate acute, pubescent. Flowers in terminal and axillary racemes, the 

 upper staminate, the lower fertile. Involucre of the staminate^florets 10-toothed, 

 10-flowered. Fruit muricate, clustered, small, obovate. 



White. <v). July— Sept. Cultivated grounds, very common. 2-6 ft. 



Genus LXVII. XANTHIUM. 



Flowers monoecious. Staminate florets, involucre imbri- 

 cate. Anthers approximate, not united. Receptacle chafFj^. 

 Fertile florets. Involucre 2-leaved, 2-flowered. Corolla none. 

 Drupe dry muricate, 2.c]eft. Nut 2-celled. 



1. H. Strumarium. Stem erect, pubescent, scabrous, angled. Leaves al- 

 ternate, cordate, usually 3-lobed, serrate, pubescent, very large, on long peti- 



