Ageratum conyzoides L., Guizotia abyssinica (L. Melampodium perfoliatum Kunth, historic urban waif. Blake, Tagetes erecta L., Thelesperma megapotamicum (Spreng.) Kuntze are waifs. Echinops sphaerocephalus L., Gaillardia aristata Pursh, Gaillardia pulchella Foug., Hymenothrix loomisii S.F. 31 for illustrations of family characteristics. Liguliflorous heads comprise only ligulate flowers. A ligulate flower is bisexual, with a bilateral, generally ephemeral corolla and 5-lobed ligule. Disciform heads superficially resemble discoid heads, with pistillate or sterile flowers that lack rays, together with or separate from disk flowers. Radiate heads have peripheral ray flowers and central disk flowers. Ray flowers are generally pistillate or sterile (occasionally lacking styles). A ray flower corolla is bilateral, generally with a slender tube and flattened petal-like ray (single lip composed of generally 3 lobes). A radiant head is a variant of a discoid head, with peripheral disk flower corollas expanded, often bilateral.

Discoid heads comprise only disk flowers. Disk flowers are generally bisexual and fertile but occasionally staminate with reduced ovaries. A disk flower has a generally radial corolla, with a cylindric tube, expanded throat, and generally 5 lobes. Note: Flower and head types differ in form and sexual condition. Genera In Family: +- 1500 genera, 23000 species: worldwide, many habitats. Fruit: achene (also called a cypsela) (drupe in Chrysanthemoides), cylindric to ovoid, sometimes compressed, generally deciduous with pappus attached. Flower: bisexual, unisexual, or sterile, +- small, of several types (see below) calyx 0 or modified into +- persistent pappus of bristles, scales, and/or awns corolla radial or bilateral (0), lobes generally (0)3-5 stamens 4-5, filaments generally free, generally fused to corolla at tube/throat junction, anthers generally fused into cylinder around style, anther base generally rounded or cordate (deeply sagittate or with tail-like appendages), tip (= flattened appendage) generally projecting beyond pollen sac pistil 1, 2-carpeled, ovary inferior, 1-chambered, 1-seeded, placenta basal, style 1, tip generally +- 2-branched (except in some staminate disk flowers), branch tips truncate or generally bearing +- brush-like appendages stigmas 2, generally on adaxial faces of style branches. Inflorescence: 1° inflorescence a head, resembling a flower, of several types (see below), 1-many in generally +- cyme-like cluster each head generally with +- calyx-like involucre of 1-many series of phyllaries (involucre bracts) receptacle of head flat to conic or columnar, paleate (bearing paleae = receptacle bracts) or epaleate flowers 1-many per head. Leaf: basal and/or cauline, alternate, opposite, rarely whorled, simple to 2+ × compound.

Cyme or panicle