283 PRACTICAL BOTANY. 



068. Pappus of cut-fringed chaiFy scales. Involucral 

 scales in one row. Leaves triple-nerved, short-petioled, 

 lieart-ovate, toothed. Heads small, rays whitish. 



Galinsoga parviflora, Cav. 

 Pappus-scales not cut-fringed 969 



969. Heads solitary on the stem or branches 970 



Heads in compound corymbs. Flowers yellow. 



Pappus of 2 awns. Stem 4-winged. Leaves ovate, triple- 

 nerved, serrate. Rays 1-5. Verbesina Siegesbeckia, Mx. 



970. Receptacle convex or conical 971 



Receptacle flat 972 



971. Achenia 4-cornered. Involucre of separate scales. 

 Heads showy, peduncled, terminating the stem or branches ; 

 rays yellow, about 10, fertile. Leaves lance-ovate, or ob- 

 long-ovate, triple-nerved, serrate. Heliopsis Isevis, Pers. 



Achenia inversely ovoid. Livolucre a leafy cup. 



Heads large, single, on terminal peduncles ; flowers pale 



yellow. Leaves oval or oblong, their bases usually connate. 



Tetragonotheca helianthoides, L. 



972. Pappus obsolete, or none. Chaff of the receptacle 

 oristle-form. Heads solitary, small, long-peduncled ; flowers 

 whitish ; anthers brown. Achenia 3- to 4-sided, or those of 

 the disk laterally flattened, hairy at the top. Stems pro- 

 cumbent. Leaves oblong-lanceolate, slightly serrate, sessile. 



Eclipta procumbens, Mx. 

 Pappus an obscure crown. Chaff of the recep- 

 tacle scale-like and rigid. Low shrubby maritime herb. 

 Heads solitary, peduncled, terminal ; flowers yellow ; an- 

 thers blackish. Achenia rather wedge-shaped, 3- to 4-cor- 

 nered. Leaves spatulate-oblong or lanceolate, silky-downy. 



Borrichia frutescens, D. C. 



973. (964.) Leaves opposite, at least the lower, or some- 

 times whorled. Rays yellow 981 



Leaves alternate 974 



974. Disk-flowers fertile, rays sterile 976 



Disk-flowers sterile, rays fertile 975 



975. Heads yellow-flowered ; rays numerous. Achenia 

 winged, sometimes with 2 teeth, Tvhich are confluent with 

 the winged margin. Corymbs or panicles. Silphiuiu (983). 



