276 PRACTICAL BOTANY. 



9^6. Scales herbaceous, often deciduous 927 



Scales scarious, mostly whitish, persistent, some- 

 times yellowish or brown 929 



9S7. Herbs. Leaves serrate. Heads heterogamous. .928 

 Scurfy shrubs. Flowers all tubular, dioecious — 

 that is, pistillate and staminate flowers in separate heads, 

 borne by different plants. Heads in loose, terminal panicles, 

 or sessile in axillary glomerules. Pappus very long and 

 white. Leaves wedge-form or spatulate-oblon^, toothed. 



Baccharis. 



928. Heads purplish, exhaling a camphor-like odor. 

 Herbs somewhat glandular. Corymbs compound, dense. In- 

 volucre imbricated. Fluchea. 



Heads whitish, corymbed. Involucre cylindrical ; 

 scales in a single row, with a few bractlets at the base. Pap- 

 pus blight wdiite and very soft. Leaves large, lanceolate or 

 oblong, unequally and deeply toothed. 



Erechthites hieracifolia, Raf. 



929. Receptable perfectly naked 930 



Receptacle (elongated, columnar, or top-shaped) na- 

 ked at the summit only, and bearing broad chafl" toward its 

 base. Heads, few-flowered, in dense, dicliotomously arrang- 

 ed clusters, woolly. Filago Germanica, L. 



930. Heads dioecions, or nearly so, corymbose, rarely sin- 

 gle. Pappus of the staminate flowers club-shaped at the 

 summit. Involucre usually pearl-white. Herbs white-wool- 

 ly. Leaves linear lanceolate. Antennaria, Gsertn. 



{Everlasting.) 



Heads containing both perfect (central) and pistil- 

 late (marginal) flowers. Bristles of the pappus all slender. 

 Herbs woolly. Leaves oblong-spatulate, lanceolate, or linear, 

 sessile, often decui-rent. Involucral scales wdiite, yellowish, 

 or brow n. Gnaphalium. 



( Cudweed.) 



931. (906.) Leaves opposite, at least the lower 936 



Leaves alternate 932 



932. Heads all alike, some of the flowers sometimes ste- 

 rile 933 



