142 COMPOSITE. [Eupatorium. 



Leaves hairy, rather stiff; radical ones ovate, mostly petiolate, those 

 of the stem oblong. Flowers purplish blue, often white. 



3. Knautia. Linn. Knautia. 



Involucellum compressed, with four little excavations, closely 

 surrounding the fruit, placed on a short stalk. Calyx with 

 a somewhat cup-shaped limb. — Name, in honour of Christo- 

 pher Knaut, a botanist of Saxony, who flourished in the 

 latter half of the seventeenth century. 



Tetrandria. Monogynia. 



1. K. arvensis, Coulter. Field Knautia or Scabious. Heads 

 many-flowered ; teeth of the crown very small ; ciliae of the 

 calyx 8 — 16, somewhat awned. Coulter. Br. Fl. J. p. 60. — 

 Scabiosa arvensis. E. Fl. v. I. p. 195. E. Bot. t. 659. 



Pastures and corn fields, frequent. Fl. July. If.. — Two to three 

 feet high. Radical leaves lanceolate, slightly serrate, hairy. Heads 

 of flowers large, convex, lilac-purple ; outer florets large, with their 

 segments unequal, the lower ones very large, and forming- a sort of ray 

 around the head ; inner florets with equal segments. Sir J. E. Smith 

 states that the fine pale purple flowers of this plant change to a most 

 beautiful green if held for a few minutes over the smoke of tobacco. 



Ord. 41. COMPOSITE. Juss. Composite Family. 



Tube of the calyx adnate with the ovary ; the limb entire or 

 toothed, or resembling scales, or mostly expanded into a simple 

 or feathery pappus, sometimes wanting. Corolla regular and 

 funnel-shaped, or irregular and ligulate, sometimes 2-lipped, ge- 

 nerally 4 — 5-toothed. Stamens 4 or 5, alternate with the teeth 

 of the corolla: anthers cohering in a cylinder. Ovary 1, 1- 

 celled, with a single erect ovule; style 1; stigmas simple or 

 bifid. Fruit an achenium, crowned with the limb of the calyx 

 or pappus. Seed erect, without albumen. Embryo straight ; 

 radicle directed to the hilum. 



Tribe I. Corymbi/era*. Juss. 



Flowers flosculous, or radiant. Receptacle membranous, or 

 not fleshy. Stigmata not articulated with the style. 



1. Eupatorium. Linn. Hemp-agrimony. 



Involucre cylindrical ; scales imbricated, oval-oblong. Florets 

 few, all tubular. Receptacle naked. Pappus pilose. — 

 Name ; from Eupator, the surname of Mithridates, King of 

 Pontus, who brought this plant into use. 



Syngenesia. uEqualis. 



