232 THE FLORA. 



Analysis of the Genera. 



Sub-order First, TUBULIFLOK^E, 



hnving all the perfect flowers tubular ( 95), the ligulate flc vers, if any, impeiteet 



Heads of flowers radiate, with yellow rays 2 



Heads of flowers radiate, the rays not yellow 8 



Heads of flowers discoid (no rays). These genera, about 50 in number, suoL a* 

 tho Tansy, Wormwood, Bonestt, Jronweed (Figs. 248-250), Everlasting, Burdock 

 (Fig. 509), Thistle, Hogweed (Fig. 514), and even Bachelor's-button, are all, for 

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



2 Leaves alternate or scattered on the leafy stems. . . .4 



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

 8 Leaves alternate or scattered on the leafy stem. . . .7 



8 Leaves opposite or whorled o the leafy stem x 



3 Leaves all radical and the flowers on a scape y 



4 Receptacle chatty (with bracts growing among the florets).... 5 



4 Receptacle with deep, horny ceiis, like a honeycomb e 



4 Receptacle not chafly, flat or merely convex. . . .a 



4 Receptacle not chaffy, conical or globular.... f 



5 Rays sterile, disk fertile. Receptacle conical or columnar. . . .g 



5 Rays sterile, disk fertile. Receptacle flattish. Fruit flattened on the sidcp ft 



5 Rays fertile, disk sterile. Receptacle flat. Fruit flattened same way as scales.... > 



6 Receptacle chafly. Rays sterile, disk fertile . . . .o 



6 Receptacle chaffy. Rays fertile, disk sterile. . . .p 



6 Receptacle chafly. Rays fertile, disk perfect . . . . q 



6 Receptacle naked or destitute of chaffy scales m 



7 Receptacle not chafly, naked of scales .... 8 



7 Receptacle chaffy with scales among the florets. Lvs. finely divided. . . ,v 



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



8 Pappus of numerous bristly hairs 9 



8 Pappus of 2 or 8 awns and minute hairs. Glabrous plants. . . .1 



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 1 



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



10 Pappus double, the outer row of hairs extremely short 



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



a Involucre not imbricated, the outer scales very short or none SENK'CIO. 



a In vol. not imbr., oufer scales equal to the inner. Marigold. CALEN'DDLA. 



a Involucre not imbricated, outer scales longer than inner. 8. GAILLAR'DIA 



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



t> Pappus double, the outer very short and chaffy. Lvs. entire. W. S. CHRYsor'eis 

 b Pappus double in the disk, none in the rays. Lvs. trothed. 8. HKTEBOTHE'OA 



