COMPOSITE 627 



Flowers. — The flowers may be perfect, polygamous, 

 monoecious or dioecious. There are two sorts of flowers in 

 the composite family: (i) Disk or tubular, and (2) ray or 

 ligulate. 



Disk Flowers (Fig. 254, C). — These are perfect and regular 

 and make up the so-called disk of the composite "flower." 

 For example, the disk of the "sunflower" is the center. The 

 calyx is modified, taking the form of a few or large number of 

 bristles, awns, scales or teeth; this modified calyx is termed 

 a pappus. In some instances, the pappus is entirely wanting. 

 It is attached to the apex of the inferior ovary. The corolla 

 is tubular and five-lobed. The five stamens are attached 

 to the corolla and alternate with its lobes; the anthers are 

 united into a tube. In one genus (Kuhnia), the anthers are 

 distinct or nearly so. The anthers are often appendaged at 

 the apex and sometimes caudate or sagittate at the base; 

 pollen grains are spherical, often rough or prickly. There 

 is a single pistil, an inferior one-celled and one-seeded ovary, 

 and a single style which is entire (in sterile flowers) or two- 

 cleft at the apex; the style branches are often tipped with 

 appendages. 



Ray or Ligulate Flowers (Fig. 254, B). — These are usually 

 imperfect and irregular. They have a pappus and a strap- 

 shaped corolla with either a long or short tube. 



The composite family is divided into two large groups, the 

 Liguliflora and Tubuliflorce. The dandelion, chicory, and 

 lettuce are representatives of the former, and sunflower, 

 Jerusalem artichoke, daisy, fleabane, aster, and goldenrod 

 typical members of the latter group. In the LiguliflorcB, 

 ligulate or strap-shaped flowers are the only sort present; in 

 these, the flowers are perfect and consist of five stamens with 

 their anthers united into a tube, a one-celled, one-seeded 

 ovary, a single style, and a two-lobed stigma; the pappus may 



