COMPOSITE. (COMPOSITE FAMILY.) 287 



x 



62. AC TIN EL LA, Pers., Nutt. 



Heads many-flowered ; rays several, wedge-oblong, 3-toothed, pistillate. 

 Scales of the hemispherical involucre ovate or lanceolate, membranaceous or 

 coriaceous, nearly equal, appressed in 2 or 3 ranks, little shorter than the disk. 

 Receptacle hemispherical or conical, naked. Achenes top-shaped, densely 

 silky-villous ; pappus of 5 or more ovate or lanceolate very thin chaffy scales. 



Low herbs, with narrow alternate leaves, dotted or sprinkled with resinous 

 atoms as in the next genus and bitter-aromatic; the solitary heads terminating 

 scapes or slender naked peduncles ; flowers yellow. (Name a diminutive 

 of Actinea, from O.KTLS, ray.) 



* Involucre of numerous distinct not rigid scales; leaves entire. 



1. A. linearifdlia, Torr. & Gray. Annual or biennial, villous or gla- 

 brate, 1 high or less, simple or branched ; leaves linear ; peduncles filiform. 



S. Kan. to La., and Tex. 



2. A. acatllis, Nutt. Perennial, densely cespitose, the branches of the 

 caudex short and thick, with scape-like peduncles, cauescently villous or silky; 

 leaves spatulate to linear, short. Hills and plains bordering the Rocky Mts. 

 and scarcely reaching our limits; the var. GiAnRA, Gray (A. scaposa, var. gla- 

 bra, Man.), a greener glabrate form, has been found on an Indian mound near 

 Joliet, 111. The less densely cespitose A. SCAP<!>SA, Nutt., more loosely villous 

 and the caudex with more slender branches, is probably in S. Kan. 



* * Scales rigid, in 2 rows, the outer connate at base ; leaves ternately parted. 



3. A. odorata, Gray. Annual, 1-2 high, branching, leafy, somewhat 

 floccose-woolly ; heads small, scattered ; leaves 1 - 3-piunately divided, the lobes 

 filiform. Central Kan. to Tex., and westward. 



63. HELENIUM, L. SNEEZE-WEED. 



Heads many-flowered, radiate ; rays several, wedge shaped, 3 - 5-cleft, fertile 

 or rarely sterile. Involucre small, reflexed, the scales linear or awl-shaped. 

 Receptacle globose or oblong, naked. Achenes top-shaped, ribbed ; pappus of 

 5-8 thin and 1-nerved chaffy scales, the nerve usually extended into a bristle 

 or point. Erect, branching herbs (ours perennial), with alternate leaves de- 

 current on the angled stem and branches, which are terminated by single or 

 corymbed (yellow, rarely purple) heads ; often sprinkled with bitter aromatic 

 resinous globules. (The Greek name of some plant, said to be named after 

 Helenus, son of Priam.) 



1. H. nudiflorum, Nutt. Somewhat puberulent, 1-3 high; leaves 

 narrowly lanceolate or oblong to linear, entire, or the radical spatulate and den- 

 tate ; heads mostly small ; disk brownish, globose ; ray yellow or partly brown- 

 purple, sterile (neutral or style abortive), shorter than or exceeding the disk. 

 (Leptopoda brachypoda, Torr. $ Gray.) 111. and Mo. to N. Car. and Tex.; 

 nat. near Philadelphia. Hybridizes with the next. June -Aug. 



2. H. autumnale, L. Nearly smooth, 1-6 high ; leaves mostly toothed, 

 lanceolate to ovate-oblong ; heads larger (about 6" broad) ; disk yellow ; ray 

 fertile, yellow. Alluvial river-banks and wet ground, Conn, to Minn., south 

 and westward. Sept. 



