245 SYNGENESIA. POLYGAM. SUPERFLU A. 
tentibus, splnosis. Recepl. favosum, subpalcaceum 
ONOPORDUM. Cal. with thorny scales : belly• 
tng. Recept. like a honey-comb, 
SERRx\TULA. Cal. subcylindricus, imbricatus; 
squamis inermibus. Pappus persistens. 
SERRATULA. Cal. nearly cylindrical', tiled: 
scales rather acute, but not thorn-like. 
# * # J 3 iscoidei. Corollulae omnes tubulosae, erec- 
to paralleli, apice planiusculi, densi. 
3 Florets all tubular. 
EUPATORIUM. Recept, nudum. Pappus sca- 
ber. Cal. imbricatus, oblongus. Stylus semibi- 
fidus, exsenus. 
EUPATORIUM. Recept. naked. Down feather¬ 
ed, Cal. tiled. Pistil very long. 
BIDENS. Recept. paleaceum. Pappus retrorsum 
scaber. CaL pojyphyllus.- Cor. subinde radiata. 
BIDENS. Recept. chaffy, Down awn-like. Cal. 
tiled. 
POLYGAMIA SUPERFLUA. 
Flosculi disci hermaphroditici; radii faemi- 
nii ; omnes tertiles. 
♦ Discoidei. Corollulae radii obsoletae.- 
1 Florets all tubular, 
TANACETUM. Recept nudum. Sem. coronata. 
Cal iinbilcatus, heimsphapricus. Flosc. radii tri- 
fidi, ubsoicti, inierdum iiulli 
