KEY. 



381 



961, (945.) Pappus none. Flowers all perfect 963 



Pappus of a few short awns or bristles, or a mem- 

 branaceous crown ,. . 962 



963. Pappus of a few short awns or bristles. Achenia. 

 wing-margined. Heads loosely corymbed, or panicled ; rays 

 white or purplish. Leaves thickish, chiefly entire. Herbs 

 Aster-like. Boltonia. 



Pappus a membranaceous margin, rather cup-like. 

 Receptacle conical. Achenia angular. Heads corymbed; 

 rays white, disk yellow. Involuci-al scales scarious-margined. 

 Leaves twice-pinnately divided. 



Matricaria Parthenium, L. 

 {Feverfew.) 



963. Rays pale violet-purple. Leaves lanceolate or ob- 

 long, or the lower spatulate-obovate. Heads solitary. 



Bellis iutegrifolia, Mx. 

 Rays white. Heads large, terminating the stem 

 and branches. Leaves pinnatifid-toothed. 



Iieucanthemum vulgare, Lam. 

 ( Ox-eye I)aisy.) 



964. (943.) One sort of the flowers in the heads, either 

 the disk- or ray-flowers sterile 973 



Disk- and ray-flowers both fertile, the latter pistil- 

 late 965 



960. Leaves opposite 968 



Leaves alternate. Rays white 966 



966. Pappus none, or a minute crown. Leaves once- or 

 twice-pinnately parted, or entire and lance-linear. Rays 

 over 4 967 



Pappus of 2 awns. Leaves ovate-lanceolate. Stem 



narrowly, or interruptedly winged. Rays 3-4, oval. Ache- 



' nia narrowly winged. Verbesina Virginica, L. (968). 



967. Achenia terete, striate or smooth. Leaves once- to 

 twice-pinnately divided. Branches terminated by single 

 heads. Anthemis arvensis, L. 



Achenia oblong, flattened, margined. Leaves 

 twice-pinnately parted, or simple and laiice-Iinear. Rays 

 4-5 or 8-12. Heads corymbose. Achillea, 



