48 DIPSACACE^E. Dipsacus. 



however, the anthesis is not simply centripetal ; the subtending bracts and those 

 of the conspicuous polyphyllous and unequal involucre spiuescent. Involucel 

 calyx-like, prismatic, truncate and crenulate at the border, enclosing the whole 

 ovary and fruit, at length adnate to its thin walls. Calyx-limb cup-like, 4-toothed 

 or lolied. Corolla tubular-funnelform, 4-lobed, nearly regular. Stamens 4. 

 Stigma lateral. Coarse and rough or prickly biennials, with cauline leaves 

 mostly connate and cup-like at base. 



D. SYLVESTRIS, MILL. Prickly, 3 to 5 feet high : leaves lanceolate-oblong : involucre longer 

 thau-the head : flowers flesh-colored : bracts of the receptacle tipped with a long and straight 

 flexilile awn. Roadsides of the Eastern States: fl. summer. (Nat. from Eu.) 



D. FULLONUM, L. (FULLER'S TEASEL.) Probably an ancient derivative of the preceding: 

 involucre usually shorter than the cylindraceous head, at length reflexed : bracts of the re- 

 ceptacle rigid-spipescent, the tips recurved or hooked ; whence useful for raising a nap on 

 woollen cloth. Escaped from cult, in some places, apparently established in S. California. 

 (Nat. from Eu.) 



ORDER LXXIII. COMPOSITE. 



Flowers in an involucrate head on a simple receptacle, o-merous or sometimes 

 4-merous ; with lobes of the epigynous corolla valvate in the bud ; stamens as 

 many as corolla-lobes and alternate with them, inserted on the tube ; anthers con- 

 nate into a tube (syngenesious) ; style in all fertile flowers 2-cleft or lobed at sum- 

 mit and bearing introrse-marginal stigmas ; ovary one-celled, a single anatropous 

 ovule erect from the base, becoming an exalbuminous seed with a .straight embryo, 

 the inferior radicle shorter and narrower than the cotyledons ; the fruit an akene. 

 Tube of calyx wholly adnate to the ovary ; its limb none, or obsolete, or devel- 

 oped into a cup or teeth, scales, awns, or capillary bristles. Corolla with nerves 

 running to the sinuses, then forking and bordering the lobes, raivly as many 

 intermediate nerves. Anthers commonly with sterile tip or appendage ; the cells 

 introrse, discharging the pollen within the tube ; this forced out by the lengthen- 

 ing of the style, which in hermaphrodite and male flowers is commonly hairy- 

 tipped or appendaged. Pollen-grains globose, echinulate, sometimes smooth, in 

 Oichoriacece 12-sided. Leaves various: no trite stipules. Development of the 

 flowers in the head centripetal ; of the heads, when clustered or associated, more 

 or less centrifugal, i. e. heads disposed to be cymose. Juice watery, in some 

 resinous, in the last tribe milky. 



Heads homoyamous when all its "lowers are alike in sex ; hetcrogamous when 

 unlike (generally marginal flowers female or neutral, and central hermaphrodite 

 or by abortion male) ; androgynous when of male and female flowers ; monoecious 

 or dioecious when the flowers of separate sexes are in different heads either on 

 same or different plants ; radiate when there are enlarged ligulate flowers in the 

 margin ; wholly ligulate when all the flowers have ligulate corollas ; discoid 

 when there are no enlarged marginal corollas. When these exist they are some- 

 times collectively called the ray : the other flowers collectively occupy the disk. 

 The head (compound flower of the early botanists), in Latin capitulum, is also 

 named anthodium. Its involucre (periclinium of authors) is formed of separate 

 or sometimes connate reduced leaves, i. e. bracts (squamce or scales of De Can- 

 dolle, &c.) : the innermost of these bracts subtend the outermost or lowest flowers. 

 The axis within or above these is the receptacle (clinanthium of some), which 



