436 ILLUSTRATIONS OF THE NATURAL ORDERS. 



of hairs, bristles, scales, &c. Corolla regular or irregular. Sta- 

 mens five, as many as the lobes or teeth of the regular corolla, in- 

 serted on its tube : anthers united into a tube {syngenesious, Fig. 

 463, 464). Style two-cleft. Ovule solitary, erect, anatropous. 

 Fruit an achenium (Fig. 568-573), either naked or crowned 

 with a pappus. Seed destitute of albumenn. Embryo straight. — 

 This vast but very natural family is divided into three series or 

 suborders ; viz. : — 



845. Snbord, Tubuliflorae. Corolla tubular and regularly four- or 

 five-lobed, eitlier in all the flowers (when the head is discoid), or in 

 the central ones (those of the dislc) only, the marginal or ray flowers 

 presenting a ligidate or strap-shaped corolla. — Ex. Liatris, Eupato- 

 rium, &c. ; where the heads are Jiomogamous, that is, the flowers all 

 tubular, similar and perfect : Plelianthus (Sunflower), Helenium, 

 Aster, &c. ; where the heads are heterogamous ; the dish floivers 

 being tubular and perfect, while those of the ray are ligidate, and 

 either pistillate only, or neutral, that is, destitute of both stamens 

 and pistils. 



846. Subord. lahiatlflorffi. Corolla of the disk-flowers bilabiate. — 

 Ex. Chaptalia, of the Southern United States ; and many South 

 American genera, &c. 



847. SuLoi'd. Ligulitloi'ffl. Corolla of the flowers (both of the disk 

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

 Cichory (Fig. 887), &c, 



848. 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 Chamomile, the 

 Boneset or Tlioroughwort, &c.) ; in others, combined with mucilage, 

 so that they arc demulcent as well as tonic (Elecampane and Colts- 

 foot) ; in many, aromatic and extremely bitter (such as Wormwood 

 and all the species of Artemisia) ; sometimes accompanied by acrid 

 qualities, as in the Tansy and the Mayweed, the bruised fresh herb- 

 age of which bhsters the skin. The species of Liatris, which abound 

 in terebinthine juice, are among the reputed remedies for the bites 

 of serpents ; so are some species of Mikania in Central America. 

 The juice of Silphium and of some Sunflowers is resinous. The 

 leaves of Solidago odora, which owe their pleasant anisate fragrance 

 to a pecuhar volatile oil, are infused as a substitute for tea. From 

 the seeds of Sunflower, and several other plants of the order, a bland 

 oil is expressed. The tubers of Helianthus tuberosus are eaten 



