276 Annals of the Carnegie Museum. 



Leaves 3-partite, the intermediate lobe lance-ovate to lanceolate, 

 gradually acuminate 722. Mikania ranunculi folia. 



Leaves trisected to three-foliolate, the intermediate lobe lanceolate 

 to sub-linear 723. Mikania corydalifolia. 



Tribe III. Astere^. 



Heads discoid or radiate, the rays pistillate. Anthers not tailed at base. 

 Branches of the style of the perfect flowers flat, smooth up to end of marginal 

 stigmatic lines, then above this more or less hairy. Leaves alternate. Receptacle 

 with no chaff. 

 Ray-flowers longer than the involucre and disk-flowers. 



Bracts of the involucre in three or more series; rays oblong; scapes simple. 



724. Aster Grisebachii. 

 Bracts of the involucre in two or three series; rays linear; scapose stems slender 

 and mostly branched. 

 Basal leaves mostly 2-4 cm. long, spatulate, narrowed to the base but not 



distinctly petiolate 725. Erigeron cuneifolius. 



Basal leaves with blades 1-2 cm. long, the petioles purple, very slender, 



and 2-4 times as long as the blades 726. Erigeron purpuripes. 



Ray-flowers shorter than the head or flowers without well-marked ligule; erect, 

 branching stems with the leaves lyrate and more or less pinnately lobed, especially 

 the lower ones 727. Conyza lyrata. 



Tribe IV. Inule^. 



Heads discoid, the pistillate flowers mostly filiform and truncate. Anthers 



sagittate-tailed at base. Style branches with obtuse or truncate mostly naked 



tips. Pappus capillary or none. 



Style-branches tapering and hairy outside for a good portion of their length. 



Leafy stemmed plants (Pluchea). 



Perennial plants. 



Stems woody; leaves entire 728. Pluchea odorata. 



Stems herbaceous; leaves serrate 729. Pluchea fcetida. 



Annuals. 



Involucres 3-4 mm. wide by 3.5-5 mm. high. 



730. Pluchea purpurascens. 



Involucres 5-7 mm. wide by 6-8 mm. high. . . .731. Pluchea camphorata. 



Leaves in a basal rosette 732. Sachsia polycephala. 



Style-branches truncate, with an apical tuft of hairs. 



733- Gnaphalium purpureutn. 



Tribe V. Helenie^. 

 Heads radiate or discoid; often yellow. Anthers not tailed. Receptacle naked. 

 Stigmas truncate or with hairy tips. Bracts of the involucre usually well imbri- 

 cated. 

 Plant tissues usually without oil-glands. 



Bracts of the involucre appressed, flowers numerous, corymbose. 



750. Flaveria linearis. 

 Involucral bracts spreading or reflexed, flowers single on a scape. 



751. Helenium scaposum. 



