84 COMPOSITE. 



and well-definable subtribes being still a desideratum, artificial sections based pri- 

 marily on the pappus are here employed.) 



Series I. Pappus none : receptacle naked. 



# Akenes truncate at base and apex, short, smooth : leaves all radical : involucre of nearly 

 nerveless bracts, nearly unchanged in fruit, rather many-flowered. 



307. PHALACROSERIS. Involucre of 12 to 16 equal and nearly herbaceous lanceolate 

 bracts, naked or loosely unibracteate at base. Akenes short-oblong, slightly incurved, 

 obscurely quadrangular : pericarp thin-coriaceous. Scape naked, monocephalous : flowers 

 yellow. 



S08. ATRICHOSERIS. Involucre of 12 or more equal lanceolate bracts, and calyculate 

 with a few minute ones. Akenes oblong, with corky pericarp, more or less 8-10-costate, the 

 alternate ribs thicker. Scape bracteate and polycephalous : flowers white and purplish. 



211. KRIGIA, & 219. MICROSERIS, very rarely want the pappus, or nearly so. 



# # Akenes, with rounded or somewhat contracted apex and small areola, narrow at base : 

 involucre of several one-nerved equal bracts, unchanged or concave-convex in fruit, 8-20- 

 flowered : corollas yellow. 



209. LAMPSANA. Involucre narrow, minutely calyculate-bracteate at base ; the true 

 bracts carinate, at least in fruit, then erect. Akenes narrowly obovate-oblong and some- 

 what obcompressed, minutely nervose-striate, smooth. Leafy-stemmed and branching Old 

 World annuals. 



210. APOGON. Involucre not calyculate, of usually 8 oblong-lanceolate herbaceous bracts, 

 in fruit becoming rather ovate by broadening of the base, concave and the tips conniving. 

 Akenes terete, obovoid, merely rounded at summit, 10-costate, obscurely scabrous-lineolate 

 transversely, rarely an obsolete vestige of pappus. Low annuals, becoming caulescent. 



Series II. Pappus paleaceous or partly so, or aristiform, or plumose. 



# Involucre simple and naked, i. e. of equal bracts and no short calyculate ones at base : 

 akenes truncate : pappus of palese and (usually) of bristles : receptacle naked. 



211. KRIGIA. Heads several-many-flowered. Bracts of the involucre thin-herbaceous. 

 Akenes short-columnar or turbinate, pluricostate, terete or somewhat angular, with bj-oad 

 truncate summit. Pappus double ; outer of pointless thin pales ; inner of delicate naked 

 bristles, these rarely wanting in one species. Flowers yellow. 



# # Involucre either calyculate or imbricated, i. e. principal bracts equal and some short 

 ones at base, or of less unequal bracts in two or more series, simple only in Tragopogon. 



+- Akenes usually short, with truncate summit (sometimes a little narrowed beneath it, not 

 rostrate) : receptacle not chaffy : flowers never yellow : caulescent, with small or reduced 

 leaves on the rigid stems or branches : flowers matutinal. 



212. CICHORIUM. Heads several-many-flowered. Involucre double; its bracts herba- 

 ceous with coriaceous and indurating base, those of the inner series partly enclosing the 

 subtended akenes, the 4 or 5 outer more spreading and herbaceous. Akenes somewhat 

 angled ; the broad summit bordered with a crown-like pappus of numerous short and blunt 

 palese, in 2 or more series. Flowers normally blue. 



213. STEPHANOMERIA. Heads 5-1 2-flowered, rarely 3-20-flowered. Involucre cylin- 

 draceous or oblong, of several appressed and equal plane membranaceous bracts and some 

 short calyculate ones, not rarely with 2 or 3 of intermediate length, thus becoming imbri- 

 cate. Akenes 5-angled or ribbed, sometimes with intermediate ribs. Pappus a series, of 

 plumose bristles, or rarely chaffy awns, not rarely naked toward the bases, which sometimes 

 are lightly connate in phalanges. Flowers pink or rose color. 



214. CH^TADELPHA. Heads about 5-flowered. Involucre of Stephanomeria, cylin- 

 draceous, the accessory calyculate bracts very small, the membranaceous proper ones 5. 

 Akenes short-linear, 5-angled, very smooth. Pappus of 5 rigid upwardly tapering awns, 

 which bear on each side toward the base 3 to 5 rather shorter and slender rigid bristles. 

 Flowers rose-color. 



-i— +- Akenes long-rostrate, base more or less excavated at insertion : receptacle naked : 

 heads rather- many-flowered : pappus a series of long-plumose bristles or awus. 



