408 



COMPOSITiE. (composite FAMILY.) 



Conyza 



Phagnalon 



Helichrysum 



Gnaphalium 



Lasiopogon 



Artemisia 



Dipterocome 45 

 Gymnarrhena 30 



Evax 6 



Micropus 7 



Xeranthemum 51 



Marginal flowerets pistillate, central perfect. 

 Receptacle chaffy, at least at edge. 

 Pappus composed of scabrous bristles 



Pappus plumose 



Pap])us none 



Pappus of 1-3 or 10 pales. Scales unarmed 

 Pappus of 8-10 pales. Scales spiny-tipped 

 Receptacle naked or covered with papillse or bristles, 

 Pappus composed of scabrous awns or bristles. 

 Plants with a woody base. 



Shrubs, 1 or more high ; leaves green ; heads 



corymbose 

 Herbs, .2 to. 5, growing in ere vices of rocks ; 



heads solitary 

 Canescent herbs or small shrubs 

 Plants not woody at base - - - - 

 Pappus plumose. Dwarf desert plants 

 Pappus none. Plants shrubby at base - 

 Marginal flowerets pistillate, central staminate. 

 Pappus scabrous ; some of the akenes 2-horned 

 Pappus of bristles and pales _ _ _ 



Pappus none. 



Outer flowerets in several rows - - - 

 Outer flowerets in one row . _ . 



Marginal flowerets neutral, central perfect. 



Receptacle chaffy 



Receptacle clothed with fringed bristles. 

 Filaments free. 



Pappus composed of bristles united in a ring 



at base 

 Pappus composed of bristles not united at 



base 



Outer pappus bristles, inner connivent pales 



Outer pappus 10 awns, inner 10 bristles 



Outer pappus in oo rows of barbellate bristles, 



inner 5-10 pales 



Filaments monadeiphous - - - - 



* * * Heads moncedous. 

 Involucre of scales grown together, covered with 



hooked prickles Xanthium 

 Involucre of unarmed heads not more than .003 broad Ambrosia 



§ 2. Heads discoid or radiate. 

 Receptacle naked. 



Pappus hairy, about 1 -rowed . . - Erigeron 



Pappus hairy, in more than 1 row - - - Senecip 

 Pappus crown-like or 0. 



Annuals or perennials. Akenes obpyramidal, 

 Annuals. Fragrant. Akenes nearly terete, 



back smooth Matricaria 

 Perennials. Akenes equally ribbed, prismatic Pyrethrum 

 Receptacle chaffy. 



Pappus consisting of plumose pales - - Atractylis 



Notobasis 



Crupina 

 Tyrimnus 



11 

 13 

 12 

 10 

 40 



60 



Phseopappus 75 

 Centaurea 72 



Cnicus 73 



69 

 65 



27 



4 

 43 



Chamsemelum 34 



38 

 37 



55 



