176 
COMPOSITE. 
[Prechthites. 
occurs occasionally in Mauritius. It is an erect obscurely -pilose 
annual, 2-4 feet high, witb fragile sulcate stems, alternate acute lanceo- 
late clasping toothed or runcinate membranous leaves, copious many- 
flowered heads twice as long as broad in dense corymbose panicles, 
involucre oblong of about 20 narrow uniserial herbaceous scales with 
a few small loose ones at the base, corollas all tubular, outer female, 
receptacle naked, anthers not tailed, minute angular-cylindrical achenes 
with a long pappus of very fine soft pure white hairs. 
19. GYNURA, Cass. 
Heads many-flowered, all the corollas tubular, all perfect, or the 
outer row female. Involucre campanulate, of 15-20 equal ligulate 
herbaceous scales, placed edge to edge, and a few small ones at the 
base. Receptacle flat or convex, foveolate. Anthers not tailed. 
Style-arms long, spreading, subulate, pilose. Achenes glabrous, cy- 
lindrical, ribbed ; pappus of very numerous long soft white hairs. 
Large annuals, with alternate membranous often runcinate leaves, and 
few distant large heads of bright purple tubular flowers. Distrib. 
Tropics of the Old World. Species about 20. Crassocepkalum, Moench, 
is an older name for the genus. 
Inner scales of involucre 20-25 . . . 1. G. cernua. 
Inner scales of involucre 12-15 2. G. pseudo-china. 
1. G. cernua, Benth. in FI. Nigr. 437. An erect annual, 2-4 feet 
high, with slightly pilose fragile sulcate branches. Leaves obovate- 
oblong, membranous, toothed, 2-4 in. long, entire or runcinate ; upper 
sessile, auricled at the base ; lower narrowed into a petiole. Heads 
cernuous, on peduncles often a foot long, with only a few small leaves, 
the upper entire, linear-subulate. Involucre \ in. long and broad ; 
inner scales 20-25, concrete at the base, and an outer circle of minute 
subulate ones at the base. Flowers above 100, the outer row often 
antherless. Achenes glabrous, slender, in. long, with a caducous 
pappus nearly \ in. long, of copious very fine soft white hairs. Senecio 
cernuus, Linn. fil. ; Bojer, Hort. Maur. 187. i Cremocephalum cernuum, 
Casa. ; DC. Prod. vi. 298, Senecio purpureus, Willemet , PI. Maur. 57. 
Mauritius, through the island in waste ground. Also Bourbon, Madagascar and 
Tropical Africa. 
2. G. pseudo-china, DC. Prod. vi. 299. An erect annual, 2-3 
feet high, with nearly naked or finely downy sulcate stems. Leaves 
alternate, obovate-oblong, 3-4 in. long, irregularly toothed, the upper 
sessile, often auricled at the base, the lower narrowed gradually into a 
short petiole, often densely pilose. Heads several to a branch, erect or 
cernuous, on much shorter peduncles than in the last and all the 
flowers perfect. Involucre f in. broad and long ; scales of inner series 
12-15, ligulate, with a lanceolate tip, shortly connate at base and a few 
