408 ORDER 70. COMPOSITE. 



ARTIFICIAL ANALYSIS OF THE GENERA. 

 A. SUBORDER, TUBULIFLORJE. 



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



1 Receptacle naked, 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) 

 2 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 Receptacle, chaffy bearing pales among the flowers. (6) 

 6 Leaves alternate, (g) 



6 Leaves opposite, (h) 



1 Receptacle bearing bristles, or deeply alveolate (honey-combed). (7) 



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

 7 Pappus composed of many bristles, (j) 



Heads radiate, i. c., the outer flowers ligulate. (8) 



8 Receptacle naked (not chaffy), or (in No. 67) deeply honeycomb-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 Hays cyanic, in a single row. (m) 

 10 Rays cyanic, in several rows, (n) 

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



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

 11 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 Rays yellow (s) 

 14 Rays cyanic, (t) 



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

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



15 Achenia obcompressed, often beaked, (v) 



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



a Corolla lobes one-sided. Head large, many-flowered STOKESIA. 2 



a Corolla lobes one-sided. Heads 4 5-flowered, aggregated ELEPHANTOPUS. 3 



a Corolla lobes equal Leaves opposite. Pappus awned AGERATUM. 4 



Leaves whorled. Pappus obtuse SCLEROLEPIS. 5 



Leaves alternate. Pappus scales 8 10 POLYPTERIS. 63 



Pappus scales 1220 HYMENOPAPPUS. 64 



b Leaves opposite. Flowers dicccious, obscure AMBROSIA. 45 



b Leaves alternate. Flowers yellow. Disk conical ! MATRICARIA. 73 



Flowers yellow. Disk convex TANACETUM. 75 



Flowers whitish. Erect, leafless above . . ADENOCAULON. 15 



Erect, leafy ARTEMISIA. 76 



Low and depressed SOLIVA. 77 



C Scales of the involucre in one row. Flowers cyanic CACALIA. 84 



C Scales of the involucre in one row. Flowers yellow SENECIO. 88 



c Scales imbricated. Flowers yellow. BIGELOVIA. 27 



Flowers whitish. EUPATORICM 1 0, and KUHNIA. S 



Flowers" purple. Pappus simple LIATRIS. 7 



Pappus double VERNONIA. 1 



d Achenia 10-striate. Flowers purple BKICKELLIA. 9 



d Achenia 5-angled. Receptacle conical. Flowers blue CONOCLINIUM. 12 



Receptacle flat. Scales 4 or 5 MIKANIA. 11 



Scales 820 . . .EVPATOKIUM. 10 



