173 
single series: pappus of few or numerous bristles or awns, sometimes chaffy at base: 
or of scales, or reduced to a chatty crown, rarely obsolete: opposite-leaved herbs. 
Tribe VI. ANTHEMIDE, Distinguished from Tribes V and VI by the more or less 
dry and searious imbricated involucral bracts: heads radiate or discoid, the perfect 
flowers sometimes sterile and the pistillate rarely tubular: achenes small: pappus 
a short crown or none: leaves alternate. 
* Receptacle chaffy, at least in part: heads radiate (rarely discoid). 
] yy P } 
+ Involucre of comparatively few broad thin bracts, 
101. Leucampyx. Involucral bracts with white-scarious margins: ray-flowers 8 
to 10, fertile, the ligule ample: achenes obovate, 3-angled: pappus an obscure chafty 
crown, soon obsolete. 
+ + Involucre of comparatively small imbricated bracts, the outer successively 
shorter. 
102, Anthemis. Achenes terete, angled or ribbed: heads hemispherical, rather 
large. 
103. Achillea. Achenes obcompressed: head small, campanulate or obovate. 
* * Receptacle naked. 
104, Matricaria. Heads rather large, pedunculate: rays pistillate or none: pap- 
pus crown-like or none. 
105. Artemisia. Heads mostly small, discoid, in panicled spikes or racemes: pap- 
pus none. 
Tribe VIII, SENECIONIDE.Z. Heads radiate or discoid, the involucre little or not 
at all imbricated, not scarious: receptacle naked: anthers tailless; pappus capillary ; 
in ours the style-branches are truncate or capitellate at tip. 
* Involucre Jax, commonly of much overlapping or unequal bracts: pappus of rather 
rigid bristles. 
+ Leaves alternite. 
106. Psathyrotes. Flowers all perfect and fertile: corollas with extremely short 
proper tube: achenes terete, obscurely striate, villous or hirsute: pappus shorter 
than corolla, of very unequal bristles. 
107, Bartlettia. Flowers all fertile but not all perfect: corollas with long and 
slender pubescent tube: achenes compressed (at maturity), with a salient nerve to 
each margin and usually on the middle of one face, these densely long-hirsute, the 
faces glabrate: pappus equalling the disk-corollas, of somewhat unequal bristles. 
+ + Leaves opposite. 
108. Haploesthes. Heads radiate and the flowers all fertile: involucre of 4 or 5 
nearly equal rather fleshy roundish bracts: achenes terete, striate-costate, glabrous. 
** Involucre of connivent-erect herbaceous equal bracts: pappus of copious soft- 
capillary bristles: leaves alternate, 
109. Senecio. Heads usually radiate: corollas yellow, 5-toothed. 
110, Cacalia. Heads discoid: corollas white or cream-colored, 5-cleft. 
Tribe IX. CyNnarorpE&. Flowers all tubular and perfect (the outer ray-like and 
neutral in no. 113): involucre much imbricated: anthers caudate, long-appendaged 
at tip: style-branches short or united, obtuse, smooth, with often a pubescent ring 
below: pappus mostly bristly: leaves alternate. 
* Achenes attached by the base: flowers all alike. 
111. Arctium. Leaves not prickly: pappus of short rough bristles: involucral 
bracts hooked at tip. 
112. Cnicus. Leaves prickly: pappus-bristles plumose: receptacle densely bristly. 
* * Achenes attached obliquely: marginal flowers often enlarged and ray-like. 
113. Centaurea. Involucral bracts appendaged: pappus double and bristly, or very 
short or none, 
