180 COMPOSITE. (composite family.) 



ers flat, smooth up to where the conspicuous marginal stigmatic lines abruptly termi- 

 nate, and prolonged above this into a flattened lance-shaped or triangular appendage 

 which is evenly hairy or pubescent outside. — Leaves alternate. Receptacle naked (des- 

 titute of chaff) in all our species. 



Subtribe 1 Asterine^. Flowers of the head all alike and perfect, or the marginal ones 

 ligulate and pistillate. Anthers without tails at the base. 



* Ray -flowers white, blue, or purple, never yellow. 



t- Pappus °f numerous long and capillary bristles : receptacle flat. 



12. SERICOCARPUS. Heads 12 - 15-flowered : rays 4 or 5. Involucre oblong or club-shaped, 



imbricated, cartilaginous. Achenia short, narrowed downwards, silky. 

 13 ASTER. Heads many flowered. Involucre loosely or closely imbricated. Achenia flattish. 

 Pappus .-iuiple. 



14. ERIGERON. Heads many-flowered. Involucre of nearly equal narrow scales, almost in 



one row. Achenia flattened Pappus simple, or with an outer set of minute scales. 



15. DIPLOPAPPUS. Heads many-flowered. Involucre imbricated. Pappus double ; the 



outer obscure, of minute stiff bristles. 

 +- -i- Pappus of very short rigid bristles, or none : receptacle conical or hemispherical. 

 10. BOLTOXIA. Achenia flat and wing-margined. Pappus very short. 



17. BELLIS. Achenia margiuless. Pappus none. Receptacle conical. 



* * Ray -flowers yellow (in one species of Solidago whitish), or sometimes none at all. 



18. BRACnTCHJETA. Heads 8 - 10-flowercd, clustered : rays 4 or 5. Pappus a row of minute 



bristles shorter than the achenium. 



19. SOLIDAGO. Heads few - many-flowered : rays 1 - 16. Pappus simple, of numerous slen- 



der and equal capillary bristles. 



20. BIGELOVIA. Heads 3- 4-flowered : rays none. Receptacle awl-shaped. Pappus simple, 



a single row of capillary bristles. 



21. CHRYSOPS1S. Heads many-flowered : rays numerous Pappus double ; the outer of 



very small chaffy bristles, much shorter than the inner of capillary bristles. 



Subtribe 2. iNtJL&S. Anthers with tails at their base : otherwise as Subtribe 1. 

 22 INULA. Heads many-flowered. Rays many. Pappus capillary. 



Subtribe 3. Baccuaride.£ fc Tarchonanthe*. Flowers of the head all tubular, either 

 dioecious or monoecious, namely, the staminate and pistillate flowers either in different 

 heads on distinct plants, or in the same head Corolla of the pistillate fertile flowers a 

 very slender tube sheathing the style, and truncate at the summit. 



23. PLUCHEA. Heads containing a few perfect but sterile flowers in the centre, and many 



pistillate fertile ones around them. Anthers tailed at the base. Pappus capillary. 



24. BACCHAR1S. Heads dioecious, some all pistillate, others all staminate, on different plants. 



Anthers tailless. Pappus capillary. 



Tribe IV. SEjVECIONIDE^E. Heads various. Branches of the style in the fertile 

 flowers linear, thickish or convex externally, flat internally, hairy or pencil-tufted at the 

 apex (where the stigmatic lines terminate abruptly), and either truncate, or continued 

 beyond into a bristly-hairy appendage. — Leaves either opposite or alternate. 



Subtribe 1 Melampodixeje. Flowers none of them perfect, but either staminate or pistil- 

 late ; the two sorts either in the same or in different heads. Anthers tailless. Pappus, 

 if any, never of bristles. 

 • Heads containing two kinds of flowers, radiate ; the ray-flowers pistillate, the central and 

 tubular staminate flowers having a pistil, but always sterile. Receptacle chaffy. 



25. POLYMXIA. Achenia thick and turgid, roundish. Pappus none. 



26. CHRYSOGONUM. Achenia flattened. Pappus a one-sided 2 - 3-toothed chaffy crown. 



27. SILPHIUM. Achenia very flat, wing-margined, numerous in several rows: rays deciduous. 

 23. PARTHENIOM. Achenia flat, slightly margined, bearing a pappus of 2 chaffy scales and 



the very short persistent ray -corolla. 



