XLITI, COMPOSITA. 223 
Florets all ligulate (LIGuULATH) . ; ; i P J 5 : : > ae 
1 Florets all tubular . 2 
Florets tubular in the disk or centre of each head, the outer ones either ligulate 
and forming a ray, or slender and filiform (CoRYMBIFER2) 5 
of Involucre i leaves prickly. Style raga bulbous under the branches 8 (Cyn. 
ROIDE#) , > : P ‘ : . 30 
; Involucre and leaves not prickly é , ; : ; ; , ; ee 
Florets purple, blue, or white , j ; : . 4 
Florets yellow or ereenish, usually small (CORYMBIFER &) , ; 5 
Leaves opposite é ; ; P ; ay 2 EupATorium. 
Leaves alternate or radical (CYNAROIDE®) : ; ‘ , i 3 d . 30 
CORYMBIFERZ. 
5 Leaves opposite ; ; : : : ; : : 5 : , are 
Leaves alternate or radical. ‘ : Z E ‘ Pray 
Flower heads few, rather large, yellow. Pappus of a few 
bristles . ll. BIDENs. 
Flower discoid, that i is, all the florets of the head tubular or filiform, the outer 
"i not longer than the central ones 8 
Flowers radiate, the outer florets ligulate and spreading, or, if erect, longer than 
[rower heads: small, numerous, purple. Pappus of many hairs 1. KUPATORIUM, 
6 
the central ones . : z tee 
8 Achenes without a pappus, or crowned by a small cup or short scales - 9 
Achenes bearing a pappus of hairs ‘ 12 
Flower-heads moncecious, the males with many tubular florets, the females 
9 forming a thick burr, ending in 2 conical beaks, and enclosing 2 flowers, 
10. XANTHIUM. 
Flower-heads all alike . - . : ; : ~ 20 
Receptacle bearing scales between the florets. Plant covered with a dense 
10} white cotton. Leaves entire or toothed . é . 16. Diotis. 
No scales between the florets. Leaves, at least the lower ones, much divided 11 
Flower-heads hemispherical, 3 or 4 lines i in diameter, in a large ‘terminal corymb. 
Achenes angular, with a flat top : é . 17. TANACETUM. 
Flower-heads small, often nodding, in a leafy raceme or panicle, Achenes 
obovate, contracted at the top . . 18. ARTEMISIA. 
Bracts of the involucre linear, equal in length, with a few very small outer 
of ones a : ; . . 13 
Bracts of the involucre imbricated in 2 or more rows . 14 
Radical leaves large, oes, heart-shaped or orbicular,. Stem-leaves small and 
is} narrow . - : : : 2 i . 19, TUssILAGo. 
Leaves pinnate and toothed . 20. SENECIO. 
Plants more or less covered with a white cotton or down.  Involucral bracts also 
cottony, or shining and scarious, or coloured at the edge . . é Ray As 
Plants not woolly. Involucral bracts narrow and green . 17 
Flower-heads dioecious. Involucral bracts with spreading tips, at least in the 
15 males , 8. ANTENNARIA. 
Flower-heads all with tubular florets in the centre. Involucres not spreading 16 
16 A row of scales within the outer row of florets . ‘ : : . 6. Fimago. 
Receptacle entirely without scales ‘ A . : . 7. GNAPHALIUM. 
All the florets tubular and 5-toothed . 2. ASTER. 
17) Onter florets of the head linear or filiform, although not longer than the cen- 
tral ones : 18 
Tall stiff plant. Flower-heads ovoid, in a terminal corymb 9. Invna Conysa. 
184 Flower-heads numerous and small, in a long leafy panicle. 
9, ERIGERON canadense. 
19 Achenes without any pappus, or crowned by a small cup or minute scales . 20 
Achenes bearing a pappus of hairs . . 24 
20 Receptacle bearing scales between the florets, at least among the central ones 21 
~ \ Receptacle naked (without scales between the flor CtSRiy yr! « . 22 
21 Flower-heads rather large, with a convex or conical receptacle 14, ANTHEMTS. 
Flower-heads small, with a small flat receptacle. ; ; eve 15) AGETELEA. 
929 Involucral bracts all green and of equallength . : ; : . 5. BELLIs. 
Involucral bracts imbricated and scarious at the edges. 24 
98 Receptacle flat or convex $d2. ‘CHRYSANTHEMUM. 
Receptacle conical, much elongated as the fruit ripens : . 138. MATRICARIA, 
