. A dictionary of the flowering plants and ferns. Botany. COMPOSITAE 165 importance in classification of the fam. It may be smooth or hairy, &c.; there may (Helianthus, &c.) or may not (Calendula, &c.) be, upon it, scaly br. belonging to the individual firs. In Cynareae these br. are divided so as to form numerous bristles. In the simplest case the fls. of a single head are all alike and §, but there are many deviations from this type. The fls. may be all actinomorphic (tubular') or all •]• (ligtilate)', see below. Very commonly however, as in daisy or sunflower, there is a distinc
. A dictionary of the flowering plants and ferns. Botany. COMPOSITAE 165 importance in classification of the fam. It may be smooth or hairy, &c.; there may (Helianthus, &c.) or may not (Calendula, &c.) be, upon it, scaly br. belonging to the individual firs. In Cynareae these br. are divided so as to form numerous bristles. In the simplest case the fls. of a single head are all alike and §, but there are many deviations from this type. The fls. may be all actinomorphic (tubular') or all •]• (ligtilate)', see below. Very commonly however, as in daisy or sunflower, there is a distinction into a disc of actinomorphic fls., and a marginal ray of-|- fls. Or, as in Centaurea sp., the outer florets may be actinomorphic but different in size from the central. The number of ray-florets varies in different sp., but according to definite rules. The distribution /" sexes among the fls. of a head varies much. The most common case is gynomonoecism, the ray-florets ?, the disc ?. The very large ray-florets of Centaurea sp. and others are completely sterile (cf. Hydrangea, Viburnum, &c.). Cf. also Tussi- lago, Petasites, &c. Tlas Jhnoer is fully epig., usu. j-merous. K absent in Ambrosia and its allies, Siegesbeckia, &c.; in some cases it appears only as a slightly -globed rim upon the top of the inf. ovary (cf. Rubiaceae and Umbelliferae); usu. it takes the form of hairs or bristles—the pappus—and enlarges after fert. into a parachute (Dandelion) or into hooked bristles (Bidens) to aid in clistr. (see below). C (5), valvate in bud; actinom. (tubular) or •[•. Of the latter form there are two varieties, labiate (lipped) and ligulate (strap-shaped). The latter term, strictly speaking, should be applied to those corollas which are strap- shaped in form with 5 teeth at the end repres. the petals, but is usu. also given to those lipped forms where the lower lip is strap-shaped and ends in 3 teeth. Sta. 5, epipet. with short filaments, alt. with
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