Ixeris 



COMPOSITAE 



Ixeris 



Key to the Species 



Stem generally with several well developed lvs. below 

 the brs. of the infl.: involucres all on short peduncles 

 in small axillary or terminal cymes: frs. deep brown 

 or blackish; pappus deciduous. 



b. Frs. without beak, 15-ribbed 1 . 



bb. Frs. beaked, 10-14-ribbed. 



Frs. 11-14-ribbed, 0.6-0. 7mm. broad, the beak 0.2- 

 0.5mm. long: cauline lvs. broadest at or near 

 the middle: anther tube and style brs. greenish 

 or blackish : fig. in the autumn 2 . 



Frs. 10-ribbed, 0.3-0.4 mm. broad, with a beak 



0.6-1 mm. long: cauline lvs. broadest at the 



base, salient-dentate or with narrowly deltoid or 



lanceolate, acuminate lobes: anther tube and 



style brs. yellow: fig. mostly in the spring 



and summer. 



Cauline lvs. coarsely dentate or pinnatifid, with 



lobes 4-15 mm. long: inner involucral bracts 



not crested or tuberculate; involucre 5.5-6.5 



mm. high 2a. 



Cauline lvs. more finely dentate, the teeth 0.5-5mm, 

 long: at least some of the inner involucral 

 bracts with a distinct tubercle or claw on the 

 dorsal surface at the apex; involucre 4.5mm. 

 high 2b. 



/. lancpolata 



I. denticulata 



ssp. denticulata 



I. denticulata 

 ssp. sonchifolia 



J. denticulata 

 ssp. elegans 



aa. Stems with 0-2 lvs. below the lowest brs. of the infl.: infl. 

 more open, always terminal: frs. yellowish, brownish 

 or reddish, always 10-ribbed or -alate; pappus persistent. 

 c. Erect or partly decumbent plants of fields and waste 

 places: lvs. lanceolate or elliptic, entire, dentate, 

 or pinnatifid: outer involucral bracts minute, 

 d. Plants not stoloniferous: involucres 6-10 mm. high: 

 frs. (including beak) 4-5.5 mm. long, 

 e. Cauline lvs., if sessile and clasping, with short, 

 obtuse or slightly acute auricles: frs. about 

 0.5mm. broad, the ribs obtuse or some- 

 what acute. 

 Cauline lvs. cordate-clasping and ciliate-dentate 

 at the base: involucres 1.2-2. 5 mm. broad 

 (in mature buds and in fr.); inner bracts 

 0.5-0.8 mm. broad; fls. yellow: frs. yellow- 

 ish or buff-colored; the beak about 1/3 

 as long as the body; pappus yellowish... 3. I. dentata 

 Cauline lvs. various: involucres 2.2-3.5 mm. 

 broad; the inner bracts 1-1.7 mm. broad: 



pappus white 4 . J . chinensis 



ee. Cauline lvs. sessile and auriculate: the auricles 

 elongate, markedly acute or acuminate: frs. 

 elliptic in outline, 0.8-1 mm. broad; the ribs 



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