408 Oedbb to.— composite. 



ARTIFICIAL ANALYSIS OF THE aHNERA. 

 A. Suborder, TUBULIFLOR^. 



S Heads discoid, that is, without rays. (1) 



1 Beceptacle iiaked^ i. e., with no pales or "bristles among the flowers. (2) 

 2 Pappus a circle of 5— 20 chaffy scales, (a) 



2 Pappus none, or a short, toothed margin, (b) 



3 Pappus composed of many capillary bristles. (3) 



3 Leaves opposite. (Heads homogamous.) (d) 

 3 Leaves alternate. (4) 



4: Heads homogamous,— fls. all perfect, (c) 

 4 Heads heterogamous, fls. not all perfect. (5) 

 5 Scales herbaceous, often deciduous, (e) 

 5 Scales scarious, persistent, often colored, (f) 

 1 Reoeptacle chaffy bearing pales among the flowers. (6) 

 6 Leaves alternate, (g) 



6 Leaves opposite, (h) 



1 Receptacle hearing bristles^ or deeply alveolate (honey-combed). (7) 



7 Pappus none, or consisting of scales, (i) 

 7 Pappus composed of many bristles, (j) 



§ HJeads radiate, i. e., the outer flowers ligulate. (8) 



8 Receptacle naked (not chaffy), or (in No. 67) deeply honeycorrib-celled. (9) 

 9 Pappus of 5-12 scales which are 1-awned or (in No. 61) cleft-bristly, (k) 

 9 Pappus none, or of a few short awns. (1) 

 9 Pappus of many capillary bristles. (10) 

 10 Eays cyanic, in a single row. (m) 

 10 Rays cyanic, in several rows, (n) 

 10 Eays yellow, in about one row. (11) 



11 Pappus double, or of very unequal bristles, (o) 

 31 Pappus simple, the bristles all similar. (12) 



12 Involucre scales imbricated, the outer shorter, (p) 

 12 Involucre scales equal, not imbricated, (r) 

 8 Receptacle chaffy^ with pales among the flowers. (13) 



13 Disk and ray flowers both fertile, the latter pistillate. (14) 

 14 Kays yellow (s) 

 14 Kays cyanic, (t) 

 13 Disk flowers sterile, ray flowers fertile, (u) 

 13 Disk flowers fertile, ray flowers sterile, (15) 



15 Achenia obcorapressed, often beaked, (v) 



15 Achenia compressed laterally, or not at all. (x) 



a C<>rolla lobes one-sided. Head large, many-flowered Stokesia. 2 



a Corolla lobes one-sided. Heads 4 — 5-flowered, aggregated Elephantopu8. 8 



a Corolla lobes equal — Leaves opposite. Pappus awned Ageeatum, 4 



—Leaves whorled. Pappus obtuse Sclerolkpis, & 



— Leaves alternate. — Pappus scales 8 — 10 Polyptkeis. 6S 



— Pappus scales 12 — 20 HYMENOPAPprs. 64 



b Loaves opposite. Flowers dioecious, obscure Ambeosia. 46 



b Leaves alternate. — Plowers yellow. Disk conical 1 Matricaria. 78 



— Flowers yellow. Disk convex Tanacetctm. 75 



— Flowers whitish. — Erect, leafless above Adenocaulon. 16 



— Erect, leafy Artemisia. 76 



— Low and depressed Soliva. 77 



Scales of the involncrein one row. Flowers cyanic Cacalia. 84 



Scales of the involucre in one row. Flowers yellow Sbnecio. 86 



c Scales imbricated.— Flowers yellow Bigelovia. 27 



— Flowers whitish. Eupatgrirttm Kuhnia. 8' 



— Flowers purple. — Pappus simple Liatrib. 7 



— Pappus double Vernonia. 1 



d Achenia lO-striate. Flowers purple Beickellia. fl 



d Achenia 5-angled. — Keceptaclo conical. Flowers blue Conoclinium. 12 



— Receptacle flat.— Scales 4 or 5 Mikania. 11 



— Scales 8 — 20 Eupatobicm. 10 



