CHAP. II. 
INFLORESCENCE. 
157 
Suppose the flowers of a simple umbel to be deprived of 
their pedicels, and to be seated on a receptacle or enlarged 
axis, and we have a capitulum or head. If this is flat, and 
surrounded by an involucre, the compound flower, as it is 
inaccurately called by the school of Linnaeus, of Compositae, 
is produced ; which is sometimes named by modern botanists 
anthodium ; it is also called cephalanthium by Richard, cala- 
this by Mirbel, calathium by Nees von Esenbeck. The 
flowers or florets borne by the capitulum in its circum- 
ference are usually ligulate, and different from those pro- 
duced within the circumference. Those in the former station 
are called Jlorets of the ray ; and those in the florets of 
the disk. 
If all the flowers are hermaphrodite in the capitulum, it is 
homogamous ; if the outer are neuter, or female, and the in- 
ner hermaphrodite, or male, it is heterogamous ; if on the 
same plant some capitula are composed entirely of male 
flowers, and others entirely of female flowers, such a plant is 
termed by De Candolle heterocephalous. 
The glomerulus or glomus is the same to a capitulum as the 
compound is to the simple umbel; that is to say, it is a 
cluster of capitula enclosed in a common involucre, as in 
Echinops. 
All the forms of inflorescence which have been as yet men- 
tioned are to be considered as reductions of the spike or 
raceme. Those which are now to be described are decom- 
positions, more or less irregular, of the raceme. 
The first of these is the panicle and its varieties. The 
simple panicle differs from the raceme in bearing branches of 
flowers where the raceme bears single flowers, as in Poa 
(fig. 78.) ; but it often happens that the rachis itself separates 
into irregular branches, so that it ceases to exist as an axis, as 
in some Oncidiums ; this is called by Willdenow a deliquescent 
panicle. When the panicle was very loose and diffuse, the 
older botanists named it ^juha ; but this is obsolete. If the 
lower branches of a panicle are shorter than those of the 
middle, and the panicle itself is very compact, as in Syringa, 
it then receives the name of thyrsus. 
Suppose the branches of a deliquescent panicle to become 
