TKEES AND SHRUBS 149 



tuse at the base; stigmas elongated: obtuse; achenes 10-ribbed or 10- 

 striate; pappus of one series of scabrous barbellate or nearly smooth 

 hair-like bristles. 



Leaves small, laciniate toothed; bracts and 

 peduncles glandular viscid; heads nearly 



sessile. 1. C. laciniatus. 



Leaves longer, truncate to cordate at base, 

 crenate dentate, not laciniate; bracts and 

 peduncles not viscid. 2. C. wrightii. 



Two other, related species doubtfully separate 

 from the last which they closely resemble 

 are C. rusbyi and C. reniformis. 



3. BACCHARIS L. 



Perennial caulescent herbs or shrubs, usually with glabrous 

 or resinous foliage below the inflorescence; leaves alternate; blades 

 often leathery, entire or toothed; haads discoid dioecious, in corymbs 

 or panicles; involucres ofter eampanulate; bracts in several series; 

 receptacle flat, pitted, naked; corollas various, staminate ones tubu- 

 lar pistillate ones filiform ; anthers entire and obtuse at base; stig 

 slender, those of the staminate flowers with broad appendages; 

 achenes flattened, ribbed; pappus various, that of staminate flowers 

 short; that of the pistillate flowers copious, of long hair-like bristles. 



Leaves very small. % inch long or loss, entire; 



plant 3 to 4 feet high. 1. />'. pteronioides. 



Leaves larger 1% to 4 or 5 inches li.-ng, not 

 fascicled, more or less toothed. 

 Plant low 2 to 3 feet high, woody only at the 

 base, leaves linear oblong, sharply and 

 nearly evenly serrate about 1% inches 

 long. 2. B. bigelovii. 



riants much taller 6 to 10 feet high; leaves 

 larger and irregularly toothed. 

 Pappus scarcely surpassing the style in fruit; 

 plant quite resinous; leaves 3 to 5 inches 



long, lanceolate! short, acuminate. 3. /.'. glutinosa. 



Pappus accrescent in fruit: leaves cuneate- 

 oblong 1 to 2 inches long with a few 

 teeth at the apex or occasionally on the 

 sides. <■ B. salicina 



4. CHRYSOTHAMNUS Nutt Rabbit Brush 



Shrubby or suffruiescent plants with narrow or terete entire 

 leaves; herbage white-tomentose or glabrous, often viscidulous or 

 resinous; inflorescence paniculate, cymose, or rarely racemose; heads 

 homogamous; involucre narrow; the bracts well imbricated usually in 

 more or less distinct vertical ranks, mostly destitute of herbaceous 



