68 Key to the System of 



335. Staminate and pistillate flowers on distinct plants; 



pappus on staminate flowers only. 



Rather small herb ; leaves narrowly .lanceolar- elliptical, 

 denticulated ; flower-headlets small, somewhat crowded 

 in panicles. Ethuliopsis. 1418 



Staminate and pistillate flowers on the same plant and 

 within the same involucre ; pappus on all the flowers 336 



336. Pappus-bristlets plumous, dilated. 



Annual herbs ; leaves narrow, entire ; flower-headlets elon- 

 gated ; fruits on very short stalklets. (Podotheca). 



Fodosperma, 1419 



Pappus-bristlets simply hair-like. 



Herbs or half-shrubs ; leaves entire; involucral bracts 



narrow; flower-headlets terminal. Ixiolaena. 1420 



337. Corollas of the marginal flowers much enlarged, some- 



times ligulate. 



Erect herbs ; leaves entire ; marginal flowers uniseriate, 

 their corollas forming a yellowish rarely purplish or 

 whitish ray ; fruit equally cylindrical; pappus con- 

 sisting of hair-like bristlets. Podolepis, 1421 



Corollas of the marginal flowers equal to the others 

 or narrower ... . ... ... ... ... 338 



338. Bracts between the flowers ... ... ... ... 339 



No bracts between the flowers ... ... ... 341 



339. Pappus conspicuous, consisting of hair-like bristlets. 



Shrubs, seldom herbs ; leaves entire ; involucral bracts in 

 several rows, often small, all appressed ; flower-headlets 

 small. Figure 84. Cassinia. 1427 



Pappus rudimentary or absent ... ... ... 340 



340. Pappus none. 



Viscid, shrubby plant; leaves narrow, entire, somewhat 

 decurrent; headlets of flowers crowded; involucral bracts 

 in several rows, rather broad, sticky, the upper from their 

 white expansipn forming a ray. Ixodia. 1431 



