jaxjmea COMPOSITE 353 



LASTHENIA 



67 Actinella Rays 8-12, pistillate : involucre of numerous bracts : recep- 

 tacle conical or convex : pappus of 5-12 hyaline entire palese. 



■*- +■ Bracts of the involucre or their tips spreading or reflexed : 

 rays cuneate, 3-5-lobed : pappus of hyaline usually awn-pointed palese, 



68 Heleniuin Eays commonly fertile : receptacle wholly naked. 



69 Gaillardia Rays neutral : receptacle with some rigid awns among the 

 flowers : achenes involucrate with villous hairs. 



Subtribe i Javanese. Involucre of broad bracts imbricated in two 

 or more series. Ligules not persistent, achenes o-angled or terete, 

 several-nerved. Many-flowered heads in ours radiate and the rays 

 fertile. 



58 JAXJMEA Pers. Syn. PI. ii, 367. 



Herbs or suffruticose plants with opposite entire leaves and 

 terminal pedunculate heads of yellow flowers. Involucre cam- 

 panulate, its bracts fleshy or membranaceous, the outer shortest. 

 Corollas glabrous. Receptacle naked. Style-branches pappillose 

 or hairy, lanceolate or short-conical at tip. Achenes all alike, 

 linear, 10-nerved, more or less angled. Pappus in exotic species 

 narrow pointed or awned 1 -nerved palese, in ours none. 



J. carnosa Gray Bot. Wilkes 360. Glabrous perennial : stems procum- 

 bent or ascending, herbaceous, leafy 6-18 inches long : leaves spatulate- 

 linear, almost terete, very feshy, about an inch long, sessile and connate 

 at base: heads erect, on short peduncles, 6 lines high : rays 6-10, linear, 

 not surpassing the disk: receptacle conical, smooth and fleshy: achenes 

 glabious, destitute of pappus. In salt marshes along the coast, Brit. Co- 

 lumbia to California. 



Subtribe ii, Heleniex. Cass. Involucre hardly at all imbricated; 

 its bracts when broad nearly equal, or in a single series. Ligules not 

 persistent, Dish]flowers numerous, ivith 5 or rarely 4 teeth or lobes. 

 Achenes few-nerved or angled, or more numerously striate-angled 

 only when turbinate or pyriform. 



* Receptacle conical beset after the achenes have fallen by project- 

 ing points. Bracts of the involucre herbaceous, in one or rarely two 

 series, commonly broad, sometimes cupulate -connate. Achenes nar- 

 row, from oblong to linear, usually tapering to the base, few-nerved 

 and angled or nerveless, not callous-margined. 



59 L ASTHENIA Cass. 



Glabrous and smooth annuals with opposite entire sessile 

 leaves and rather small heads of yellow flowers terminating the 

 branches. Heads radiate, or discoid by diminution of the 

 ligules; disk-flowers all fertile. Involucre a single series of 

 herbaceous bracts united by their edges into a 5-15-toothed cup. 

 Disk-corollas 4-5-lobed, with rather slender tube and dilated 

 throat. Achenes linear or narrowly oblong, compressed, slight- 

 ly 2-3-nerved or nerveless, nearly marginless. Pappus of 5-10 

 subulate firm paleae, or none. 



