Part 80 (1/2)

14. Chrysopsis. Heads many-flowered; rays numerous. The outer pappus of very small chaffy bristles, much shorter than the inner of copious capillary bristles.

[=][=] Pappus simple.

15. Aplopappus. Heads many-flowered, many-radiate. Involucre hemispherical. Pappus of many unequal bristles. Western.

16. Bigelovia. Heads 3--4-flowered; rays none. Receptacle awl-shaped.

Pappus a single row of capillary bristles.

17. Solidago. Heads few--many-flowered; rays 1--16. Pappus of numerous slender and equal capillary bristles.

18. Brachychaeta. Heads 8--10-flowered, cl.u.s.tered; rays 4 or 5. Pappus a row of minute bristles shorter than the achene.

[*] 2. Ray-flowers white, blue, or purple, never yellow.

[+] Pappus none or very short, with or without a few awns.

[++] Receptacle conical. Awns none.

19. Bellis. Achenes marginless, flattened; pappus none. Involucral scales equal.

20. Aphanostephus. Achenes prismatic; pappus coroniform. Outer scales shorter.

[++][++] Receptacle flat or convex. Pappus usually with awns.

21. Chaetopappa. Achenes fusiform; pappus of 5 or fewer thin chaff and alternating awns. Western.

22. Boltonia. Achenes very flat, thick-winged; pappus of short bristles and usually 2--4 awns.

[+][+] Pappus of a single row of awns or coa.r.s.e rigid bristles, or in the ray scale-like.

23. Townsendia. Low or stemless, with linear-spatulate leaves and large aster-like flowers.

[+][+][+] Pappus of numerous long and capillary bristles; receptacle flat.

24. Sericocarpus. Heads 12--20-flowered; rays 4 or 5. Involucre oblong or club-shaped, imbricated, cartilaginous. Achenes short, narrowed downward, silky.

25. Aster. Heads many-flowered, on leafy peduncles. Involucral scales unequal, loosely or closely imbricated. Achenes flattish; pappus simple (rarely double), copious.

26. Erigeron. Heads many-flowered, on naked peduncles. Involucre of narrow equal scales, little imbricated. Achenes flattened; pappus simple and rather scanty, or with some outer minute scales.

[*] 3. Rays none. Heads dicious (all pistillate or all staminate).

27. Baccharis. Heads many-flowered. Pappus capillary. Smooth glutinous shrubs.

Tribe IV. INULOIDEae. Heads discoid (radiate only in Inula), the pistillate flowers mostly filiform and truncate. Anthers sagittate, the basal lobes attenuate into tails. Style-branches with unappendaged obtuse or truncate naked tips. Pappus capillary or none.

[*] 1. Receptacle naked. Involucre not scarious, imbricated. Not woolly.

28. Pluchea. Heads containing a few perfect but sterile flowers in the centre, and many pistillate fertile ones around them. Pappus capillary.

[*] 2. Receptacle chaffy. Involucral scales few, mostly scarious. Low floccose-woolly annuals; flowers as in n. 28.