220 THE FLORA. 
ant, when all the florets are ligulate (Fig. 504) ; discoid, when all the florets 
are tubular, there being no rays (Fig. 509). The receptacle is the broad 
top of the stalk on which the florets sit (Fig. 499). Itis chag’y when there 
are scales or bracts growing among the florets, and naked when none. 
The tubular florets constitute the disk, and the ligulate, if any, the ray ; 
the disk is generally yellow, while the ray is about as often cyanic (that is, 
blue, red, white, or any color except yellow) as yellow. 
Fig 498. A Sunflower,—head radiate. 9. Vertical secition of the head, showing the scales of 
the involucre, and a single disk-flower remaining upon the convex receptacle. Fig. 500. A per- 
fect disk-fl..wer magnified, showing the acheninm, the 2 awns of the pappus, the 5-toothed tu- 
bular corolla, the 5 stamens united around the branched style, and the chaff-scale at base. 1. Head 
(radiate) of Solidago cesia, 2. A pistillate, Hgulate flower of the ray. 8, A perfect disk-flower. 
4 A (radiant) head of Dandelion. 5. A perfect, ligulate flower. 6, Achenium, with its long 
beak and feathery pappus. 7. A (radiant) head of Nabalus altissimus, 8. A flower. 9 Luppa 
(Burd ck), head discoid. 10. A flower. 11. One of the hooked scales. 12. A (discoid) head of 
Eupatorium purpureum. 13. A flower. 14. Ambrosia (Pigweed). 15. Staminate head enlarged. 
16, Pistillat involucre enlarged. 17. The fertile fower, 
