COMPOSITAE A465 
kinds of flowers it is called heterogamous and when only one kind, homo- 
gamous. 
1, Flowers all tubular or campanulate, no ray-flowers present. 
2. Flowers homogamous, that is, all perfect and alike. 
3. Heads few to many, many-flowered, not crowded in dense involucrate 
masses or spicately arranged. 
4. Involucral-bracts in several series. 
5. Pappus of long hairs. 
6. Style-arms, slender, hairy............-.-..---cssos2e--cessceneneese 1. Vernonia 
6. Style-arms glabrous or nearly S0.............--.---.-+-+ 2. Eupatorium 
& \Pappus of G6 wwned scales: 8 ieee 3. Ageratum 
4. Involucral bracts in a single series................2.2-.:cssse-eeeeeeee* 4. Emilia 
3. Heads few-flowered, fascicled, forming dense, often subcapitate and 
involucrate clusters, or in pairs and spicately arranged. 
5. Elephantopus 
2. Flowers heterogamous, the outer ones female, the inner ones perfect. 
8. Heads arranged in dense, globose, peduncled masses; branches 
OS RR Ss lit Se ane 8 ER Bil a 6. Sphaeranthus 
8. Heads not arranged in globose masses, corymbose, panicled, or 
racemose. 
4. Pappus of numerous soft hairs. 
5. Herbs, often coarse and shrub-like; involucral scales narrow; 
SS ESE SEL cs eee ee a elec 7. Blumea 
5. Low shrubs with slender stems and pale-purple flowers; in- 
MGLESERL~ DEacts . DEOAG....:.....-..ue a Ee ee 8. Pluchea 
4, Pappus none, cup-like, or of scales or spines, not hairy. 
5. Pappus represented by a bristly or toothed, cup-like ring. 
9. Grangea 
5. Pappus of small lacerate or divided scales .... 10. Crossostephium 
5. Pappus of spines terminating the angles, 2 to 3 times as long 
SE Se RN o> teas enc Pap ca cocina ecmen canes 11. Synedrella 
5. Pappus none. 
6. Rather coarse aromatic herbs with numerous heads. 
12. Artemisia 
6. Slender, prostrate or spreading, very small herbs with solitary 
heads. 
7. Heads short-peduncled; anther-cells tailed........ 13. Epaltes 
7. Heads sessile; anther-cells not tailed.............. 14. Centipeda 
1, Ray-flowers present, 1 or more outer rows ligulate, the disk-flowers 
tubular. é 
Fi PAappee.Ot aaw  ueAbian ys UBITS 50.0. cial. ee hee 15. Erigeron 
2. Pappus of awns or scales, or none. 
3. Pappus cupular, scale-like, or none. 
4, Involucral-bracts united; rank scented cultivated herbs with large 
Welle wl iowa Soi aio... bee 16. Tagetes 
4. Involucral-bracts free or nearly so. 
5. Receptacle smooth or pitted, not paleaceous.. 17. Chrysanthemum 
5. Receptacle paleaceous. 
6. Outer 4 bracts large, foliaceous, in opposite pairs. 
18. Enhydra 
6. Bracts all similar, or at least the outer 4 not foliaceous. 
111555——30 
