Order 70.— TUBULIFLOR^. 221 



Analysis of the Genera, 



Sub-order First, TUBULIFLOK^, 

 having all the perfect flowers tubular (§ 05), the ligulate flowers, if any, imperfect. 



§ Heads of flowers radiate, with yellow rays. , . .2 



§ Heads of flowers radiate, the rays not yellow 3 



§ Heads of flowers discoid (no rays). These genera, about 50 in number, such aa 

 the Tansy, Jl'onmvood, Boiies^t, Ironweed (Figs. 24S-250), Everlasting, Burdock 

 (Fig. 50y), Thistle, Jlogiveed (Fig. 514), and even Bachelor'' s-hutton, are all, for 

 want of room, omitted. (See Class Book of Botany, p. 410, &c.) 



2 Leaves alternate or scattered on the leafy stems 4 



2 Leaves opposite or whorled on the stems, or all radical. . . .6 

 3 Leaves alternate or scattered on the I'eafy stem. . . .7 



3 Leaves opposite or whorled on the leafy stem x 



3 Leaves all radical and the flowers on a scape y 



4 Eeceptacle chaify (with bracts growing among the florets) 5 



4 Keceptacle with deep, horny cells, like a honeycomb e 



4 Keceptacle not chafty, flat or merely convex a 



4 Eeceptacle not chafly, conical or globular.. . .f 



5 Kays sterile, disk fertile. Eeceptacle conical or columnar g 



5 Kays sterile, disk fertile. Keceptacle flattish. Fruit flattened on the sides. . , .h 

 5 Kays fertile, disk sterile. Keceptacle flat. Fruit flattened same way as scales. , ..k 



6 Keceptacle chaffy. Kays sterile, disk fertile.... o 



6 Keceptacle chaffy. Kays fertile, disk sterile p 



6 Keceptacle chaffy. Kays fertile, disk perfect q 



6 Keceptacle naked or destitute of chaffy scales m 



7 Keceptacle not chaffy, naked of scales. . . .8 



7 Keceptacle chaffy with scales among the florets. Lvs. finely divided t 



7 Keceptacle chaffy with scales, &c. Lvs. undivided, merely toothed.... w 



8 Pappus of numerous bristly hairs 9 



8 Pappus of 2 or 3 awns and minute hairs. Glabrous plants t 



8 Pappus wholly wanting, or only a membranous margin.... u 



9 Involucre of unequal scales, imbricated in several rows.... 10 

 9 Involucre scales nearly equal, narrow, and almost in one row.. ..t 



10 Pappus simple, the bristly hairs abundant and about equal r 



10 Pappus double, the outer row of hairs extremely short s 



a Involucre scales imbricated in several rows. . . .b 



a Involucre not imbricated, the outer scales very short or none Sexe'cio. 

 a Invol. not imbr., outer scales equal to the inner. Marigold. Calen^ddla. 

 a Involucre not imbricated, outer scales longer than inner. S. Gaillak'dia 



b Pappus simple, the bristles all equal and of one kind o 



b Pappus double, the outer very short and chaffy. Lvs. entire. W. S. Chrysop'sIs 



b Pappus double in the disk, none in the rays. Lvs. toothed. S. IIeterotue'ca 



