BUDS AND BRANCHES 143 
duncle, from which they spread in every direction like the 
rays of an umbrella, as the name implies. This is the preva- 
lent type of flower cluster in the parsley family, which takes 
its botanical name, Umbellifere, from 
its characteristic 
form of inflores- Shap 
cence. The pedi- 2 
cels of an umbel 
are called rays, and 
the circle of bracts 
at the base of the 
cluster is an invo- 
¥1e. 169. —Corymb oes 
of lies hia. 162. Determi- 
nate, or cymose, 
inflorescence. — In the cyme, the typical cluster of the de- 
terminate kind, the older blossoms in the center, being ter- 
minal, stop the axis of growth in that direction and force the 
stem, in continuing its growth, to send out side branches 
from the axils of the topmost leaves, in 
a manner precisely gp¢ 
similar to the two- ,gl' 
forked branching of % i >r\ 
stems like the horse- 
« chestnut and jimson 
- weed. When the older 
peduncles are length- 
ened as described in 
161, a flat-topped cyme 
is produced, which is 
distinguished from the 
Fie. 170. — Umbel of milk- 
weed. 
Fic. 171. — Panicle . 
of grass, a compound corymb by its order of 
cluster of the racemose flowering, the oldest Fic. 172. — Flat-topped 
type. cyme of sneezeweed. 
blossoms being at the 
center, while in the corymb they appear in the reverse 
order. A peculiar form of cyme is found in the scorpioid 
