COMPOSITE. (composite FAMILY.) 209 



Tribe II. EUPATORIACE^E. Heads discoid ; the flowers all tubular and 

 perfect : branches of the stijle, usuallj/ elomjuted, club-shaped, minutely pubes- 

 cent ; the stigmatic lines obscure. — Flowers while, blue, or purple. 



4. AGERATUM, L. 



Heads many-flowered. luvolucre uearly hemispherical ; the scales numer- 

 ous, imbricated. Receptacle naked or chaffy. Acheuia 5-augled. Pappus 

 composed of 5-10 distinct scales, or a mere border. — Leaves opposite, 

 toothed. Heads in close corymbs. Flowers blue or purple. 



1. A. littorale. Gray. Stem diffuse, somewhat shrubby at the base, 

 smooth ; leaves ovate, abruptly contracted into a slender petiole ; corymbs 

 few-flowered ; receptacle naked ; pappus a whitish truncated margin. — Bouth 

 Florida. — Stem 1° - 2° long. Flowers blue. 



2. A. COnyzoides, L. Leaves ovate, rhombic, or cordate, on rather 

 long petioles ; scales of the pappus 5, slightly serrate, awu-pointed from a 

 broad base. — Wet places near Savannah, Georgia. JVIay. — Pubescence and 

 form of the leaves variable. Flowers white or blue. 



5. HARTWRIGHTIA, Gray. 



Heads few-flowered. Scales of the involucre in 2 rows, linear, obtuse. 

 Receptacle naked. Corolla dilated above, 5-toothed. Anthers appendaged. 

 Acheuia 5-angled. Pappus none. — A glabrous perennial herb. Stem corym- 

 bose above. Leaves alternate, obtuse, entire, obscurely veined, the lower ob- 

 long, tapering into a long margined petiole, the tipper few, small and distant, 

 linear. Heads C}' mose, pedicelled. Flowers white, resinous-punctate, like the 

 achenia and involucre. 



1. H. Floridana, Gray. — Sphagnous marshes, Volucia County, Florida 

 (Wright, Webster). — ^tem 2° -3° high. Leaves, with the petiole, 6'- 12' 

 long. 



6. SCLEROLEPIS, Cass. 



Heads many-flowered. Scales of the involucre linear, imbricated in 2 

 rows, equal. Receptacle naked. Corolla 5-toothed. Achenia 5-angled. 

 Scales of the pappus 5, almost horny, oval. — A smooth aquatic perennial 

 herb, with whorled linear leaves, and 1-3 heads of purple flowers terminating 

 the stem or peduncle-like branches. 



1. S. verticillata, Cass. — Shallow ponds. July. — Stems asceuding, 

 1° high. Leaves 5- 6 in a whorl. Heads f wide. 



7. CARPHEPHORUS, Cass. (Liateis, Ell.) 



Heads many-flowered. Scales of the involucre imbricated in 3-5 rows, 

 ovate or lanceolate, appressed. Receptacle chaffy. Achenia 10-ribbed. 

 Pappus of numerous unequal bearded bristles. — Erect perennial herbs. 

 Leaves alternate. Heads corymbed. Flowers purple. 



1. C. Pseudo-Liatris, Cass. Pubescent and somewhat hoary; stem 

 8im])le, rigid ; leaves linear, appressed, the lowest crowded, elongated ; corymb 

 small, dense, mostly simple ; pedicels bracted ; scales of the involucre lance- 



14 



