COMPOSITE. 55 



yellow, wanting only in certain species (much reduced and inconspicuous in a section 

 of Erigeron and one of Aster). Receptacle naked (not paleaceous), with an occasional 

 exception. 



* Pappus of both disk and ray none or corouiform. 



-)— Involucre broad, many-flowered : rays numerous, fertile, conspicuous. 



35. BELLIS. Bracts of the involucre nearly equal in length, herbaceous or somewhat 

 inenil)rixiiaceous. Receptacle conical or hemispherical. Style-branches tipped with a short 

 triangular appendage. Akenes obovate and compressed, nerveless except at the margins. 

 Pappus uuue. 



36. APHANOSTEPHUS. Bracts of the involucre imbricated in few series, broadly 

 lanceolate, somewhat herbaceous with scarious apex and margins, the outer shorter. Recep- 

 tacle conical or hemispherical. Style-branches with a very short and obtuse appendage. 

 Akenes prismatic or terete, truucate : the broad apex bordered with a short corouiform and 

 either dentate or entire and minutely setulose-ciliate pappus. Base of corolla-tube often 

 skirrous-tliitkened in age. 



37. GREENELLA. Bracts of the involucre imbricated in a few series, the outer shorter, 

 all oblong, coriaceo-cliartaceous, with scarious margins and an herbaceous dorsal tip. Re- 

 ceptacle flat, barely convex. Style-branches witli a linear rather obtuse appendage, which 

 is four times the leugth of the quadrate stigmatiferous portion and much exserted. Akenes 

 short, somewhat turbinate, obscurely 8-uerved, hispidulous. Papjjus a hyaliue-scarious 

 crown cleft into numerous setulse or denticulations. 



-i— -K- Involucre narrower and flowers less numerous. 



38. KEERLIA. Involucre narrowly campanulate or turbinate ; its bracts imbricated in 

 few series, of unequal length, oblong, smooth, thin-membranaceous with scarious margins, 

 mostly setaceously mucronate. Receptacle small and flat. Rays 5 to 15, with oblong ligule 

 ou a slender tube. Style-appendages either short and obtuse or long and slender. Akenes 

 obovate and compressed or subclavate, 2-3-nerved, and with very small epigynous disk; 

 those of the disk-flowers mostly sterile. Pappus minute and corouiform or evanescent from 

 the mature akenes. 



# * Pappus of solitary or few setiform awns or bristles and of a few paleae or a crown : 

 rays conspicuous, fertile : akenes without wings or callous margins : receptacle flat or 

 nearly so. 



39. CH-^TOPAPPA. Involucre several-many-flowered, cam])auulate or narrower; its 

 bracts oblong or lanceolate, thin-herbaceous, with scarious margins and tip, imbricated in 

 two or more ranks, the outer shorter. Rays 5 to 20 ; the ligule oblong, raised on a slender 

 tube. Disk-flowers often sterile : their style-appendages short. Akenes either fusiform or 

 compressed, 2-5-nerved. Pappus of five or fewer thin and nerveless short palea3, alter- 

 nating with as many or fewer mostly long and setiform scabrous awns, or the latter some- 

 times wanting. 



40. MONOPTILON. Involucre many-flowered, broad ; its numerous bracts equal and 

 almost in a single series, narrowly linear, somewhat herbaceous. Rays numerous ; the ligule 

 obovate or oblong and with a rather long tube : this and the tube of the disk-corolla sparsely 

 villous. Style-appendages triangular and obtuse. Akenes oblong-obovate, compressed, one- 

 nerved at each margin, or the outermost also on one face. Pappus both in disk and ray a 

 short and cupuliform barely denticulate crown, and a single setiform awn which is barbellate 

 or plumose toward the apex. 



* * # Pappus short-setulose or squamellate and mostly biaristate, i. e. a ring of very short 

 bristles or setiform squaniellai and a pair of naked ujjward-tapering awns, one o^'er each 

 edge of the broad and flat winged or callous-margined akene : involucre many-flowered, 

 hemisplierical or broader ; the bracts somewhat herbaceous and thin-margined : recep- 

 tacle strongly convex or low conical : rays conspicuous, fertile ; their akenes occasionally 

 3-wiuged. 



41. DICH^TOPHORA. Involucre somewhat uniserial; tlie lanceolate bracts of equal 

 length. Style-appendages of the disk-flowers triangular-lanceolate. Akenes surrounded by 

 an almost orbicular firm wing, its edge and tlie Itody of the akene glochidiate-hispid. 

 Pappus of two divergent awns about half the length of the akene, and of several minute 



