630 COMPOSITAE 
resemble a calyx and the florets rest upon a base, the receptacle, 
which may be flat, convex or concave, and which, when the florets 
are removed may present a naked surface or may be occupied by 
bristles or scales or filled with small pits. The individual florets 
are of two kinds, those which occupy the center of the group and 
which in some tribes constitute the whole group, are tubular like 
little blue-bells, the corolla of one piece, with 5 lobes enclosing a 
style in the center and usually 5 stamens in a ring about it. 
Below the corolla and stamens is the ovary of a single cell, which 
produces a single seed. The calyx is not always present, but when 
present is represented not by the green sepals common in many 
flowers, but by an aigrette of fae or bristles, by teeth, awns or 
scales. The flowers a the periphery, in most of the genera, differ 
from the central florets in that the corolla is prolonged on one 
side forming a ray or strap-like organ which is conspicuously white 
or colored. Of this important family not less than 10,000 species 
are known. 
SYNOPSIS OF TRIBES 
Receptacle not chaffy 
Florets all of one kind, tubular, the corolla of one piece, 
regular, 5-pointed. Flowers purple, heads in spreading 
clusters. Branches of the style long, slender, bristly all 
Over’ ic . TRIBE 1, VERNONIEAE 
Florets all of one kind, wi stamens and pistils, the style 
thickened above, blunt, not bristly . TRIBE 2, EUPATORIEAE 
Heads without ray florets (except Inula, which has large ray 
flowers) Anthers arrow-formed, the basal lobes extended into 
tls. . . TRIBE 4, INULEAE 
Florets mostly of ay are ul in some species all ‘altos 
when not all alike the outer, ray, flowers are pistillate. 
Anthers not tailed, obtuse at base; receptacle naked. 
Branches of the style flat, prolonged into a lance-shaped 
appendage. Bracts of the involucre decidedly overlap- 
DIRS ae te . . . TRIBE 3, ASTEREAE 
Florets as in Tribe 4, but branches of style either w ith hairy 
tips or the tips terminate bluntly. Bracts of involucre 
overlapping . . . . TrIBe 6, HELENIEAE 
Florets of the disk th. style the branches of which are pro- 
vided with a tuft of hairs. Aigrette of soft bristles. Bracts 
of the involucre only slightly, if at all, overlap- 
PING. os oh a ue ea) ae a) om 6 RLBE SO, ONG 
