2. _Fasciculate-ciliated_, when the hairs are collected into tufts. (Fig.
17, antenna of _Chloroclystis plinthina_.)
3. _Pubescent_, when the antennæ are clothed with uniform short hairs.
(Fig. 19.)
The functions of the antennæ are still a matter of dispute amongst
entomologists. The majority of the older naturalists regarded them as
organs of hearing. The antennæ are almost always more fully developed in
the male than in the female. From this circumstance many modern
entomologists consider that one of their functions is to enable the former
to find the latter.