184 COMPOSITK FAMILY. 



.M. ++++++ H-t- ^Aenes incurved or hoat-shaped, rough-tubercled on the back : no pap. 

 pus ; rays numerous in more than one row : Jlowers all yellow or orange. 



48. CALENDULA. Heads showy, solitary teraninating the branches, with the very 



numerous rays pistillate and fertile, expanding in sunshine or bright daylight; 

 the disk-flowers sometimes few in the centre and sterile. Involucre of nu- 

 merous short green scales. Receptacle flat. Akenes all that mature belong- 

 ing to the ray-flowers, strongly incurved, some of them even horse-shoe- 

 shaped, or coiled into a ring, and (especially the outer ones) with thickened 

 margins. 



H— M- ^ chajfon the receptacle behind each Jlower. 

 ** Only the ray-flowers fertile or maturing their akenes ; those of the disk, even if 

 apparently perfect, always sterile: flowers all yellow. Coarse tall herbs. 



49. POLYMNIA, Heads rather small or middje-sized, with about5 leaf-like scales- 



to the involucre, and some thin and small inner ones, few or several ray- 

 flowers producing turgid obovate or paiily triangular akenes with no pappus. 

 Herbage clammy-pubescent and rather sti'ong-scented : all bu^ the upper- 

 most leaves opposite, and their petioles winged or dilated and stipule-like at 

 the clasping base. 



60. SILPHIDM. Heads mostly large, with numerous somewhat leafy-tipped or 



gi-een scales to the involucre imbricated in 2 or more rows, numerous ray- 

 flowers producing very broad and flat akenes (parallel with the scales of tlie 

 involucre), which have commonly a wing-like mai'gin and 2 teeth or a notch 

 at the top. Juice resinous. 

 ++ 4-f Bisk-flowers perfect and fertile, those of the ray pistillate and fertile or neutral. 



a* Akenes flattened parallel with the scales of the involucre and chaff of tlie recep- 

 tacle, or in 53 sometimes very slender. Leaves generally opposite : involucre 

 double, the outer mostly leaf-ltke, the inner of erect scales. 



61. DAHLIA. Eays in the natural flowers neutral or in tlie common species more 



or less pistillate, but in the gardens most or all of the flowers are changed into 

 rays. Inner involucre of numerous more or less united scales. Akenes 

 oblong, obscurely 2-horned or notched at the apex. 



62. COREOPSIS. Rays usually 8, neutral, mostly yellow,.or brown-purple at base. 



Involucre commonly of about 8 outer loose or leaf-like scales and as many 

 erect inner ones. Chaff slendei', deciduous with the flat akenes, which have 

 mostly a pappus of 2 teeth or awns, the latter not barbed downwai-ds. 

 53. BIDENS. Like Coreopsis, but several without rays, and some with slender or 

 needle-shaped akenes ; aU bear 2 or more rigid persistent awns, which are 

 barbed downwards ! 



b. Akenes flattened if at all contrary to the scales if the involucre and the clinfnf 

 the receptacle, having tlie latter usually embracing or folded round their outer 

 margin. 



= Rays deciduous after fowering, yellow, sometimes brown-purple at base in 60, 61, 

 or white in one oj 56. Leaves either opposite or alfimate in same aenus, in 

 54-66. ■' 



64. ACTJNOMERIS. Rays neutral, few or several. Involucre of several nearly 

 egual scales. Receptacle convex or conical. Akenes flat, oval, wing-mar- 

 gmed: pappus of 2 persistent smooth awns. Leaves simple, serrate, often 

 decurrent into wings on the stem. 



55. VERBESINA. Rays few (in ours 1-5), pistillate. Involucre of few erect 

 scales. Receptacle rather flat. Akenes flat, winged or wingless: pappus of 



Kc ^?T,F^lzi?lf} ^^??^' ^^'^""^^ simple, decurrent into wings on the stem. 



68. AIMENliblA. Rays numerous, pistillate. Scales of the involucre spreading. 

 Receptacle flattish or convex. Akenes of the rav wrinkled and wingless; 

 those of the disk flat and wing-margined, with two slender awns united to 

 the wing. Leaves mostly with winged petioles which are dilated and clasp- 

 mg at the base. 



b1. HELIANTHUS. Rays, several or many, neutral. Sc.iles of the involucre im- 

 bricated. Receptacle flat or convex. ' Akenes flattish, more or less 4-angled 

 or lenticular, marginless: pappus of 2 thin chafiy scales corresponding with 

 the outer and inner angle of the akene, and sometimes with minute' inter- 

 mediate ones, all deciduous from the ripe fruit. (Lessons, p. 130, fig. 293.) 



TT-rf?X';?cf'™P'°' ™''™°'"*®''™'®' stems not winged. 

 58. MLLIOl SIS. Rays 10 or more, pistillate. Scales of the involucre in 2 or 3 

 rows, the inner shorter than the disk. Receptacle conical. Akenes 4-angled, 

 somewhat cubical: no pappus. Leaves opposite, petioled, triple-ribbed. 



