THE MONOPETALOTJS ORDERS. 



433 



I 



811. Ord, Composite (the Composite or Sunflower Family). Herbs 

 or shrubs ; with the flowers in heads (compound flowers of the 

 older botanists), crowded on a receptacle, 

 . ^ A A A A anc ^ surroun ded by a set of bracts (scales) 

 !' i wpWW^ forming an involucre ; the separate flowers 

 1 often furnished with bractlets (chaff, pale a). 

 I 111 I Limb of the adnate calyx obsolete, or a 

 pappus (305), consisting of hairs, bristles, 

 scales, &c. Corolla regular or irregular. 

 Stamens five, as many as the lobes or teeth 

 of the regular corolla, inserted on its tube : 

 anthers united into a tube (syngenesious, Fig. 769). Style two- 

 cleft. Fruit an achenium, with a single erect exalbuminous seed, 

 either naked or crowned with a pappus. Embryo straight. This 

 vast but very natural family is divided into three sets or suborders ; 

 namely : 



812. Sllbord, Tubuliflorffi, Corolla tubular and regularly four- or 

 five-lobed, either in all the flowers (when the head is discoid),* in 

 the central ones (those of the disk) only, the marginal or ray-flow- 

 ers presenting a ligulate or strap-shaped corolla. Ex. Liatris, 

 Eupatorium, &c. ; where the heads are homogamous, that is, the 

 flowers all tubular, similar, and perfect: Helianthus (Sunflower), 

 Helenium, Aster, &c. ; where the heads are heterogamous ; the 

 disk flowers being tubular and perfect, while those of the ray are 

 ligulate, and either pistillate only, or neutral (473, note), that is, 

 destitute of both stamens and pistils. 



813. Subord, Labiatiflorse, Corolla of the disk- flowers bilabiate. 

 Ex. Chaptalia, of the United States, Mutisia, Chsetanthera, &c., 

 of South America. 



814. Subord, Ligllliflorae, Corolla of all the flowers (both disk 

 and ray) ligulate ; all perfect. Ex. The Dandelion, Lettuce, 

 Cichory, &c. 



815. This vast family comprises about a tenth part of all Phse- 

 nogamous plants. A bitter and astringent principle pervades the 

 whole order ; which in some is tonic (as in the Camomile, Anthe- 

 mis nobilis, the Boneset, or Thoroughwort, Eupatorium perfoliatum, 

 &c.) ; in others combined with mucilage, so that they are demul- 

 cent as well as tonic (as in Elecampane and Coltsfoot) ; in many, 

 aromatic and extremely bitter (such as Wormwood and all the spe- 



FIG. 769. Syngenesious stamens of a Composita. 770. The anthers laid open. 



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