COMPOSITE FAMILY. 169 
Receptacle n naked. 
Pappus of slender but rather stiff bristles. Flowers °® 
— or Ld oi Beat of involucre several. 2. EvPAToRIUM. 
Pa of very s weak naked bristles. Flowers r 
Be En ow. #22. SENECIO. 
#* Flow two kinds in the same heads. 
Marginal flowers mit pie sterile, commonly enlarged. 23. CENTAUREA. 
Marginal oe Las spt and fertile. 
Receptacle naked or bearing no conspicuous chaff. 
: amen s vot capillary bristles. Scales of the involucre imbri- 
cated, dry and scarious. 20. GNAPHALIUM. 
sues tt "of capillary bristles. Involucre of but one row of 
eren, y small. #5. ERIGERON. 
Heads large. Ppa lis copious, very white. 21 ERECHTHITES. 
Pappus iar or none. 
Akenes broad at the top. Si oe a short crown. 18. TANACETUM. 
Ake: on S narrow at the top. -Pappus none. 19. ARTEMISIA. 
nds in separa’ te heads ; one pistillate, the other 
eee ta tel of two ki 
remade 
Heaters 
Fertile paanpelll small Paina pointed and often tubercled. ! 
| Fertile involucre an -oblon ng Pr prickly bur, 2- sone’, 2-seeded. 9. XANTHIUM. 
ers, or some of them, 
, the margi 
of capillary bristles. ' (Rays all pistillate.) 
Rays pocunsing # pb rows. 
Heads solitary upon a scape. 3. TUSSILAGo. 
Heads more or ~~ oe bed. , #*#5, ERIGERON. 
White he tate or ‘on never P hopes Pappus simple. 
Yellow, of _ same color as disk. 
Scales of the in semper ne row. Pappus soft and weak. **22. SENECIO. 
yolu cs) ppu 
Scales ¢ inyolucre imbricated. Pappus simp] 
Heads small, racemed or clustered. 6. Sormpaco, 
ge, ing the bran 7. INULA. 
ches. 
** Pappus none, or a cup or crown, or 2-3 — teeth or chaffy scales 
corresponding with the angles or edges of the akene, often with inter- 
vening minute bristles or — es. 
Akenes terete or enced: Pappu none. Receptacle flattish. 17, LEUCANTHEMUM. — 
ptacle chaffy. 
Rays ewe (rarely Distillate but sterile) ; the disk flowers perfect. 
Rece — et convex or columnar, and 
Chatty only at the summit ; the shalt decides. 
Pappus coil 14. Marvra. 
Mom minute 
enes 4-sided, flat at the Pappus none, or a i 
on ‘ 10. Ruppecxza. 
Aken nes os flattened laterally. Pappus of 2 deciduons scales. 11. Hetiayravs. 
Akenes flat, wing-margined, bearing 2 persistent awns. 12. ActivomERis. 
ee flat. A 
a ee Seen 4-sided, with 2 or more downwardly barbed ca sc enen c 
13. Boexss, 
pistillate e fertile, | as ven as the disk flowers. 
Akenes flattened and mar aren, ined. Pappus none. 16. 
— rem sig or Receptacle convex or conical. "Leaves 
orga 
