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NATTFEAL HISTOEY OE 
nine or ten, and in some cases, instead of being 
conical, they are globose and somewhat remote from 
each other, being connected by a slender filament, 
so that they bear no unapt resemblance to a series 
of beads rather loosely strung. The ordinary length 
may be stated to be about half that of the body, but 
they very often fall short of these dimensions, and 
in many insects they are not longer than the head. 
On the other hand, they often equal or surpass the 
length of the insect, and in the Capricorn-beetles, 
a tribe distinguished by the length and delicate 
structure of these members, they are sometimes 
more than four times as long as the body. Al- 
though of considerable importance in the systematic 
arrangement of insects, the development of the an- 
tennas does not seem subjected to any very general 
or well-established rules, and is therefore of less 
value than certain other parts of structure. For 
example, we frequently find a considerable differ- 
ence to exist in the form of the antennae among 
species in other respects intimately allied ; and even 
between the sexes of the same species a great dis- 
parity of size and structure is observable. When a 
difference exists, those of the male are more fully 
developed than those of the female. 
The antennae are obviously of the first importance 
in the economy of insects, but their primary use 
has not been fully ascertained. It seems to be ge- 
nerally admitted that in many tribes they exercise 
