GARDEN BOTANY. 



Ivu 



No strap-shaped flowers, but with, a ray of enlarged and cleft 



tubular flowers 



Flowers all tubular and alike : scales of the involucre fleshy. 

 Pappus of several, or more than 2, conspicuous chaffy scales, 



which are often awned or bristle-pointed. 

 Rays none : flowers all alike, tubular, mostly blue. . 

 Rays or marginal strap-shaped flowers conspicuous, yellow, or 



partly brown or purple. 



Involucre of separate leafy scales : leaves not punctate- 

 Involucre a solid cup : strong-scented herbage glandular- 

 punctate with coarse pellucid dots 



Pappus none, or a small cup, or of only 2 teeth, scales, or awns. 

 Heads with rays or larger strap-shaped flowers round the mar- 

 gin, or in cultivation sometimes all the corollas changed 

 into such (double) flowers. 



Achenia incurved, rough, not flattened : flowers yellow. 

 Achenia not incurved except in Coreopsis. 

 Involucre double, of few scales, the outer different from 

 the inner, each in one row or nearly : leaves opposite. 

 Ray-flowers many in the cultivated varieties. . 



Ray -flowers, 6 or 8, broad, neutral : achenia compressed. 

 Involucre not double, but usually imbricated. 

 Receptacle bearing chaffy scales among the flowers. 

 Rays persistent without fading, paper-like, pistillate. 

 Rays not persistent, 



Neutral : pappus of 2 deciduous chaffy scales. 

 Neutral : pappus a little cup or none. Man. p. 214. 

 Pistillate, numerous, elongated. . ... 

 Pistillate, few, short and broad. 

 Receptacle naked, i. e. no chaff among the flowers. 



Receptacle conical 



Receptacle flat or convex 



Heads without any obvious rays, 



Rose-colored or white : a quilled state of the Daisy. . 

 Orange, large, with a leafy and spiny involucre. 

 Yellow or greenish, small, not prickly : strong-scented plants. 

 Pappus a minute cup or none : heads hemispherical. 

 Pappus none : heads globular, very small. . 



18. CENTAUREA. 



19. CYNARA. 



1. AQERATUM. 



8. GAILLARDIA. 



9. TAGETES. 



10. CALENDULA. 



6. DAHLIA. 



7. COREOPSIS. 



4. ZINNIA. 



6. HELIANTHUS. 

 RUDBECKIA. 



12. ANTHEMIS. 



13. ACHILLEA. 



3. BELLIS. 

 11. CHRYSANTHEMUM. 



3. BELLIS. 

 17. CARTHAMUS. 



14. TANACETUM. 



15. ARTEMISIA. 



* * Juice of the stem milky : flowers all perfect and urith strap-shaped corollas. 



Pappus a row of many short scales united into a cup or crown : 



flowers 20 or less, blue, ephemeral. . Man. p. 235. CICHORIUM. 



Pappus of 5 to 7 long and pointed scales : scales of the involucre 



scarioufi, imbricated : flowers blue. . ... 20. CATANANCHE. 



Pappus of many strongly plumose stout bristles : achenia long- 

 beaked : flowers purple or purplish. .... 21. TRAGOPOGON. 



Pappus a tuft of soft and white smooth hairs : achenia flat, with 



a long and slender beak : flowers yellow. ... 22. LACTUCA. 



1. Ageratum conyzoides, var. Mexicanum, is a tender annual, with 

 ovate and cordate pubescent and veiny opposite leaves, and loose corymbs of 

 small heads of sky-blue flowers ; the most prominent part of these consists 

 of the club-shaped styles. 



