640 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM, 
Leaves entire or toothed, the teeth never spine-tipped. 
Bracts of the involucre longitudinally striate. 
22, OLIGONEURON (p. 666), 
Bracts not longitudinally striate. 
Plants low, cespitose, with short woody stems; leaves evergreen; 
heads solitary, long-pedunculate....23. SteNotus (p. 666). 
Stems wholly herbaceous; leaves not evergreen; inflorescence 
various. 
Bracts, at least the outer, foliaceous or with prominent folia- 
ceous tips. 
Disk flowers tubular; plants with tap-roots. 
24, Pyrrocoma (p. 667). 
Disk flowers widened upward; plants not with tap-roots, 
Heads corymbose; rays few; plants tall. 
25, OREOCHRYSUM (p. 667). 
Heads solitary; rays numerous; plants low. 
26. Tonestus (p. 667). 
Bracts not foliaceous, or merely with green tips. 
Rays more numerous than the disk flowers; receptacle fim- 
briolate; heads corymbose..... 27. EurHamia (p. 667). 
Rays not more numerous than the disk flowers; receptacle 
_alveolate; inflorescence various. 
Inflorescence racemose or paniculate; bracts not in ver- 
tical rows; basal leaves not rigid nor sharp-pointed. 
28. Sorpaco (p. 668). 
Inflorescence corymbose; bracts in distinct vertical rows; 
basal leaves rigid, sharp-pointed. 
29, Perraponia (p. 671). 
Tribe IV. GNAPHALIEAE. 
Plants not woolly, tall, usually 1 meter or more. 
Stems woody; leaves sericeous; pappus bristles of sterile flowers with thickened 
LIPS... 2. eee ee eee eee eee 44. BERTHELOTIA (p. 693). 
Stems herbaceous; leaves not sericeous; pappus bristles not thickened at the tips. 
45, PLucHea (p. 693). 
Plants woolly, much less than 1 meter high, seldom more than 40 cm. 
Receptacle chaffy. . 
Bracts of the receptacle inclosing the achenes and falling with them, hyaline- 
appendaged.................2.2---2-------- 46, STYLOCLINE (p. 693). 
Bracts merely subtending the achenes, persistent, not hyaline-appendaged. 
47. Evax (p. 693). 
Receptacle naked. 
Plants not dicecious; flowers fertile throughout the heads. 
48. GNAPHALIUM (p. 694). 
Plants dicecious or the pistillate heads with a few perfect flowers in the 
center, 
Pappus bristles of pistillate flowers falling separately, those of the stami- 
nate flowers scarcely clavellate; perfect flowers present in the 
centers of pistillate heads.........:...... 49. ANAPHALIS (p. 695). 
Pappus bristles of pistillate flowers falling in a ring, those of the stami- 
nate flowers clavellate; central perfect flowers none. 
50, ANTENNARIA (p. 695). 
