COMPOSITE FAMILY 239 
100. COMPOSITA. Composite Famry 
Flowers epigynous, in a dense head, on a common recepta- 
cle, surrounded by an involucre composed of many bracts 
(Fig. 29), with usually 5 stamens inserted on the corolla, 
the anthers united into a tube which surrounds the style. 
Fic. 29. Flower cluster and flowers of yarrow 
A, flower cluster; B, section of flower cluster; C, a ray flower; D, a disk 
flower. a, anthers; ch, chaff of disk; d, disk flowers; 0, ovary; rc, corollas 
of ray flowers; s, stigmas; fc, corolla of tubular flower. (4, B, C,7 times 
natural size; D, 18 times natural size) 
Calyx with its limb sometimes wanting; when present taking 
the form of scales, bristles, ete., Known as pappus (Fig. 30). 
Corolla either strap-shaped (Fig. 29, 7c) or tubular (Fig. 29, tc); 
in the former case often 5-toothed, in the latter usually 5- 
lobed. Style 2-cleft above. Fruit an akene, often provided 
with means of transportation. This is the largest family of 
flowering plants and among the most specialized for insect 
