ETTPATOEITTM. PETASITBS. 187 



many, oblong. Fr. truncate, not beaked, with a very short 

 crenulate margin. Pappus brittle. 



lAnomalous Genus. Order AMBRosiACBiE Link.J 



[48. Xanthium. Heads moncecious. — Male : inv. of 1 row 

 of free phyll., many-flowered. Receptacle scaly. Cor. 

 funuelshaped, 6-cleft. Anth. free. Stigma blunt, entire. 

 — ^Fem. fl. 2, enclosed within the inv. which ends in 1 — 2 

 beaks, is covered with hooked spines, and hardens over the 

 fruit. Cor. 0. Stam. 0. Stigmas 2, diverging, linear. 

 Fr. compressed, each occupying a cell in the involucre.] 



Suborder!. TUBULIFLORM. Flowers all tubular, 

 regular, with 4 — 5 teeth ; or the outer ligulate. 



Tribe I. Eupatoriem. 



Fl. all tubular, regular, perfect. Anth. not tailed. Style- 

 branches blunt, terete, subclavate. 



1. Etjpatq'eium Linn, Hemp- Agrimony. 



1. E. cannab'inum (L.) ; 1. in 3 or 5 deep lanceolate serrate 

 segments the middle one longest. — JE. B. 428. — St. herbaceous, 

 erect, striate scabrous, 2 — 3 feet high. Heads in a fastigiate 

 corymb, 5 — 6-flowered. Phyll. about 10; 5 exterior short, 

 blunt. Florets reddish purple. L. downy. Herb slightly 

 aromatic. — Banks of streams. P. VHI. IX. E. S. I. 



Tribe II. Tussilaginem. 



Fl. of ray female, filiform or ligulate ; of disk male, tubular. 

 Anth. not tailed. Style-branches connate or short, with conical 

 tips. 



2. Petasi'tbs Oaert. Butterbur. 



1. P. mdgdris (Des£) ; 1. roundish-cordate unequally toothed 

 downy beneath with approximate basal lobes, stigmas of the 

 submale fl. short ovate, female fl. truncate obliquely. — R. xvi. 

 901. Tussilago Petasites L. E. B. 430, 431. — Soboliferous. 

 Panicle loDg and lax in the female plant, ovoid and dense in the 

 male. Fl. appearing before the 1., on stout erect stalks which 

 are clothed with concave tumid petioles either leafless or with 

 a small limb. L. very large, radical, ultimately often 3 feet 

 broad, glabrous above. — Swamps. P. IV. E. S. I, 



