THE INFLORESCENCE 
63 
minates in a flower. The oldest flowers are thus those 
furthest away from the apex of the main shoot, and the 
order of opening of the flowers is centripetal. This inflo- 
rescence is also frequently called indefinite or indeterminate , 
because the first axis does not, as a rule, end in a flower; 
exceptions occur however in Aconitum and other Ranun- 
culaceae, &c. Good examples of the simple raceme occur 
in Ribes, Cruciferae, Berberis, Prunus sp., &c. 
If instead of each branch bearing but a single flower, it bear another 
raceme, we get a compound raceme or panicle , as seen in oats and 
many other grasses; the terms applied to inflorescences are, however, 
very loosely used, and the name panicle is given to any inflorescence 
presenting this loosely branched appearance, whether the branching be 
racemose or cymose, or both. If in the simple raceme the flowers be 
imagined all sessile, we get the simple spike , as in Plantago. This also 
may be compounded ; true compound spikes occur in wheat and other 
grasses, &c. ; often, however, the secondary branching is cymose. In 
.practice the name spike is given to all elongated inflorescences of sessile 
flowers, whatever the branching. A variety of the spike is the catkin , 
amentum , or pendulous spike, seen in hazel, oak, chestnut, &c. If we 
imagine the stalks of all the lateral flowers of a raceme to grow as fast 
as the main axis, we get a simple corymb , with all the flowers at one 
level, as in candytuft (Iberis) and other Cruciferae. The name is also 
given to all branched inflorescences whose flowers stand at about the 
same level. If we imagine the corymb to have its main axis ‘condensed* 
so that all the stalks of the individual flowers spring from one point — 
its summit — we get the umbel . This is usually compound, as seen in 
Umbelliferae, and may be cymose (see below). Lastly, if the flowers 
of the umbel be imagined sessile, the summit of the stalk being enlarged 
into a common receptacle to bear them, we get the head or capitulum , as 
seen in Compositae; this too may be compound, as in Echinops, &c. 
In the sympodial or cymose inflorescences, the general 
principle underlying their variety is that each branch, when 
formed, ends in a flower after bearing a few leaves (brac- 
teoles), usually one or two in number. From the axils of 
these leaves the branching is continued. The term definite 
or determinate is often applied to inflorescences of this type, 
to indicate this peculiarity of the branching. The inflor- 
escence (termed generally a cyme) is built up of a number 
of ‘short shoots,’ which frequently form a true straight 
sympodium (p. 42), especially in the older (fruiting) part 
of the inflorescence. If each successive branch bear upon 
itself one new branch only, the cyme is termed monochasial , 
if two, dichasial , if more, pleiochasial. 
