CHAP. II. 
INFLORESCENCE. 
133 
bears a single flower, as in Eryngium, the umbel is said to be 
simple (Jig. 80. a) ; but if they divide and bear other umbels, 
as in Heracleum, the umbel is called compound ; and then 
the assemblage of umbels is called the universal umbel, 
while each of the secondary umbels, or the umbellules, is 
named a partial umheL The peduncles which support the 
partial umbels are named radii. Louis Claude Richard con- 
fined the word umbel to the compound form, and named the 
simple umbel sertulum {bouquet) ; but this was an unnecessary 
change. 
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, named glomus by some, 
glomerulus by others. 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 often named by modern botanists anthodiiLm ; it is also called 
cephalanthium by Richard, calathidium by Mirbel, calathium 
by Nees von Evenbeck. The flowers or florets borne by the 
anthodium in its circumference are usually ligulate, and differ- 
ent from those produced within the circumference. Those in 
the former station are called florets of the ray ; and those in 
the XoitleY, florets of the disk. 
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. 81.) ; 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 difllise, the 
older botanists named it a juba ; but this is obsolete.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 
K 3 
