220 



THE FLORA. 



ant, when all the florets areligulate (Fig. 504) ; discoid^ when all the florets 

 are tubular, there being no rays (Fig. 509). The receftade is the broad 

 top of the stalk on which the florets sit (Fig. 499). It is chaff ij when there 

 are scales or bracts growing among the florets, and naked when none. 



The tubular florets constitute the di&\ 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 4riS. A Sunflower, — bead radiate. 9. Vertical secition of the head, showing the scales of 

 the involucre, and a single disk-flower remaining upon the convex receptacle. Fig. b\)\). A per- 

 fect disk-flower magnified, showing the achenium, the 2 awns of tlie pappus, the 5-toothed tu- 

 bular corolla, the 5 stamens united around tlie brimched style, and the chafif-scale at base. 1. lie id 

 (radiate) of Solidago caesia, 2. A pistillate, ligulate 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 Nabalns altissimus. 8. A flower. 9. Luppa 

 (Burd ck), head discoid. 10. A flower. 11. One of the hooked scales. 13. A (discoid) head of 

 Eupatoriuni purpureum. 13. A flower. 14. ^w&rcs/a (Pigweed). 15. Staminate head enlarged. 

 16. Pistillat involner<i enlarged. 17. The fertile flower. 



