Palmacce. 459 
Palms, like all other Endogenous plants, scarcely increase in 
diameter, that is to say, they do not add to their size by concen- 
tric woody layers, but the trunk merely lengthens and consoli- 
dates as it unfolds new leaves. The flowers are either unisexual 
Fig. 221. Livistona australis. 
or hermaphrodite and individually small and inconspicuous, but 
commonly exceedingly numerous and arranged on large 
branching spadices enclosed in a foliaceous spathe, which opens 
when the flowers are about to expand. The entire inflorescence 
of some species is of immense proportions. The structure of 
the flowers is tolerably uniform, being composed of 6 perianth- 
segments in two more or less distinct series, and from 3 to 
