104 



KEY TO THE FAMILIES AND GENERA 



KB. Style-branches Bubterete, obtuse, 

 covered with minute papilla;: Ivs. 

 opposite or alternate: anthers sub- 

 entire at base 2. EUPATORITM 



AA. Heads with all perfect or some imper- [TRIBE. 



feet fls., with or without rays and 

 often yellow. 

 B. Anthers tailed. 



c. Style-branches linear: heads with 



or without rays 3. INCLA TRIBE. 



cc. Style-branches united or short; 

 heads without rays ; typically 

 with spiny or scarious appen- 

 daged, many-bracted involucre 



and fleshy receptacle 4. CTKARA TRIBE. 



BB. Anthers not conspicuously tailed. 

 c. Style-branches in disk-fls. flattened 

 out, and with a distinct though 

 sometimes very short terminal 



appendage 5. ASTER TRIBE. 



cc. Style-branches not flattened out. 



NOTE. It is impossible to make a key to separate the follow- 

 ing tribes from one another. Some of the important characters 

 are italicized: 



Receptacle chaffy or rarely naked under 

 the sterile disk-fls. : style-branches 

 truncate or appendaged or the style of 

 the sterile fls. undivided; pappus some- 

 times absent but generally of 2-4 awns, 

 which are slender or somewhat chaffy 

 and with or without intermediate 

 scales which are free or connate at base: 

 Ivs. opposite, rarely alternate 6. HELIANTHCS 



Receptacle naked; style-branches truncate [TRIBE. 



or appendaged; pappus usually chaffy, 

 rarely of awns or bristles, or absent: 

 Ivs. opposite or alternate: intolucral 

 bracts in 1 or B series, rarely 3-4, her- 

 baceous or membranous: herbage often 

 resinous-dotted 7. HELENIUM TRIBE. 



Receptacle chaffy or naked ; style- 

 branches truncate; pappus when pres- 

 ent crown-shaped, rarely of short chaff: 

 Ivs. mostly alternate: involucral bracts 

 in 2 or more series, dry or scarious at 

 apex 8. ANTHEMIS TRIBE. 



Receptacle usually naked; style-branches 

 truncate or appendaged ; pappus 

 usually of bristles: Ivs. mostly alternate: 

 inner involucral bracts in 1 series, sub- 

 equal, the outer ones small or wanting, or 

 rarely all imbricate in numerous series. . 9. SENECIO TRIBE. 



Receptacle naked; style-branches trun- 

 cate or the style of the sterile fls. un- 

 divided ; pappus absent or wool-like: 

 ITS. usually alternate or radical: involu- 

 cral bracts in 1-2 series, subequal, nar- 

 row 10. CALENDULA TRIBE. 



Receptacle naked, chaffy or alveolate; 

 style-branches rounded at apex, obtuse 

 or rarely truncate or the style of the 

 sterile fls. undivided; pappus absent, or 

 chaffy or crown-shaped : Ivs. radical 

 or alternate: involucral bracts in an 

 indefinite number of series, often scar- 

 ious at apex or spinescent 11. ARCTOTIS TRIBE. 



Series 2. LABIATJEFLORVE. Corollas of 

 all or only of the bisexual fls. bilabiate 12. MUTISIA TRIBE. 



Series 3. LIGULIFLOR.E. Corollas all 

 ligulate and fls. bisexual: juice milky 13. CICHOHILM TRIBE. 



//. Artificial Key to the Composite Tribes. 



(Condensed from Engler & PrantL) 



A. Plants without milky juice: corolla of 

 disk-fls. not ligulate (except some of 

 the Mutisia Tribe, recognized by the 

 peculiar style and caudate anthers). 

 B. Style below its point of branching 

 neither thickened nor with a ring 

 of long sweeping hairs. 

 c. Anthers not caudate. 



D. Style-branches awl-shaped, 

 acute, minutely hairy outside 

 and often on style below, stig- 

 matose over the whole inner 



face VERNONIA TRIBE. 



DD. Style-branches subterete, ob- 

 tuse, covered with minute 

 papilhe, .stigmatose in 2 lines 



near the base EUPATORIUM TRIBE. 



ODD. Style-branches flattened, with 

 distinct though often short- 

 terminal, usually short-hairy 

 appendages, stigmatose in 2 

 lines ASTER TRIBE. 



DDDD. Style-branches flattened, stig- 

 matose in 2 lines, very diverse 

 in form (i. e., truncate or ap- 

 pendiculate, but with a dis- 

 tinct tendency toward a ring 

 of long sweeping hairs some- 

 where above the fork (transi- 

 tions frequent to the above 3 

 tribes). 



E. Pappus not capillary, but 



composed of scales, plumose 



bristles, or strong awns, or 



crown-like or wanting. 



P. Involucral bracts without 



scarious margins, rarely 



with narrow membranous 



margins (in some genera 



which may be separated 



by strongly developed 



scaly pappus from the 



Anthemis Tribe). 



o. Chaff present HELIANTHUS THIBE. 



GO. Chaff absent HELENIUM TRIBE. 



FP. Involucral bracts scarious 

 margined: pappus or 

 reduced, sometimes uni- 

 laterally developed ANTHEMIS TRIBE. 



BE. Pappus capillary, simple SENECIO TRIBE. 



DDDDD. Style-branches of the bisexual 



fls. (which are sterile) almost 



or quite wanting, rarely of 



normal size, not stigmatose. 



E. Plants more or less completely 



dioecious: chaff 0. 

 F. Involucral bracts in 1 row, 

 of equal length (often with 

 tiny bracteoles at the 



base) Petasites. 



FF. Involucral bracts in many 



rows Baccharis. 



EE. Plants not dioecious: heads 



bisexual. 

 F. Chaff 0. 



a. Achene of female fls. 



with pappus of coarse 



or fine bristles or hairs, 



sometimes plumose. 



H. Involucral bracts in 



several rows 



Some members of ASTER TRIBE. 

 HH. Involucral bracts in 1 

 row, separate, with 

 tiny bracteoles at 



base Tussilago. 



HHH. Involucral bracts in 1 



row, connate at base. Othonna and 

 GG. Achene of female fls. with [Gamolepis. 



scaly pappus Gulierrezia. 



GGG. Achene of female fls. with 



no pappus. 

 H. Lvs. opposite or 



radical Osteospermum. 



HH. Lvs. alternate 



Some members of CALENDULA TRIBE. 

 FF. Chaff present. 



G. Involucre not scarious, 

 nor woolly (see Milani- 

 podinese and Ambro- 

 sie of the Helianthus 

 Tribe). 



GG. Involucre scarious mar- 

 gined ; inner bracts 



woolly Eriocephahis. 



cc. Anthers caudate. 



D. Style-branches awl-shaped, 

 acute, minutely hairy outside 

 and often on style below, stig- 

 matose on whole inner face. . . 



Members of VERNONIA TIIIBE. 

 DD. Style-branches otherwise. 



E. Limb of corolla of bisexual fls. 

 5- (rarely 4- ) toothed or 

 -lobed, rarely, in the Inula 

 Tribe, slightly 2-lipped. 



F. Plants dioecious Antennaria. 



FF. Plants not dioecious. 



G. Heads with filiform fe- 

 male marginal fls., or 



fls. all alike. Some members of INULA TRIBE. 

 GG. Heads with fls. of 2 sexes: 

 corolla of female fls. 

 (marginal) ligulate, 

 rarely tubular, with 

 broad regular or 2- 

 lipped limb. 



H. Pappus present 



Some members of INVLA TRIBE. 

 HH. Pappus CALENDULA TRIBE. 



