CICHORIACEJS COMPOSITE 387 



97 Hypochoeris Flowers yellow : pappus a series of fine plumose bristles 

 with or without some naked and shorter outer ones. 



<------ Receptacle not chaffy : achenes either truncate at sum- 

 mit or upwardly attenuate, yet with no distinct or prolonged beak : 

 pappus of awnecf or pointed scarious palese, or of awns or bristles with 

 paleaceous base, or plumose. 



98 Ptilocalais Perennial herbs with biennial fusiform and more or less 

 branching and leafy stems : pappus of 15-20 white and soft plumose 

 bristles with paleaceous base. 



99 Microseris Annual or j erennial herbs with branching leafy stems : 

 pappus of 4-10, usually 5 palese tapering into scabrous awns. 



100 Scorzonella Glabrous perennials with leafy stems from fusiform 

 roots : pappus of 5-10 bristles with small paleaceous base. 



101 Uropappns Acaulescent or su bcaulescent annuals: pappus of 5 

 scarious bidentate awn-tipped palese. 



102 Nothocalais Acaulescent perennials: pappus of 20-25 linear-lan- 

 ceolate silvery-white palese in 2 or more series. 



3 Pappus of capillary bristles scabrous, rarely barbellate, 

 never plumous nor rose-tinted : except in Rafinesquia. 



* Receptacle with or without some capillary bristles among the 

 flowers. 



103 Malacothrix Achenes terete: pappus soft and white, promptly de- 

 ciduous, mostly together. 



* * Receptacle naked. 



-*- Achenes not flattened : pappus persistent, or the bristles tardily 

 falling quite separately. 



** Beak of the achene none, or a mere attenuation. 



104 Apargidium Heads solitary, terminating simple brae tless scapes : 

 achenes columnar, truncate, not tapering at either end: pappus 

 brownish, of soft and rather fragile capillary bristles. 



105 Hieracium Achenes oblong or columnar, mostly 10- ribbed or 

 striate : pappus tawny, of rather rigid scabrous fragile bristles in a 

 single series. 



106 Crepis Achenes from columnar to fusiform, 10-20-costate : pappus 

 white and soft, in 2 or more series. 



107 Nabalus Achenes terete or 4-5-angled, linear-oblong or cylindrical : 

 pappus of copious rather rigid capillary bristles. 



108 Lygodesmia Achenes terete, linear or slender-fusiform : pappus of 

 copious and usually unequal capillary bristles. 



*+ ** Beak of the achene distinct, usually slender : heads always erect. 



109 Agoseris Involucre more or less imbricated in more than 1 series : 

 achenes 10-costate or 10-nerved. 



110 Taraxacum Involucre of a single series : achenes 4- or 5-costate or 

 angled and usually with some intervening nerves. 



111 Rafinesquia Achenes terete, obscurely few-ribbed : pappus of 10-15 

 slender softly long-plumose bristles. 



*- *- Leafy-stemmed plants with more or less paniculate heads: 

 achenes flattened : pappus of copious fine and soft capillary bristles. 



