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accidental in the first instance, has been availed of by the insect, 
and found favourable for more effectually carrying out the purposes 
to which the antennze are put; and further development has 
ensued. We are still ignorant as to what those purposes are; 
nor is it likely that we should ever know them. Even supposing 
insects to have the same senses that we have, their organs of 
sense may be constructed quite differently. Their ranges of sight 
and hearing may be entirely outside the ranges by which our 
own vision and hearing are limited. They may see objects clearly 
by the help of a few scattered rays of light such as would be to 
us no light at all; they may hear sounds utterly inaudible to 
human ears. Their sense of touch, in like manner, may be so 
delicate as to enable them to distinguish things, and slight 
differences in things, whether animate or inanimate, where we 
should feel absolutely nothing. Lastly, who shall say there may 
not be other senses than those we are possessed of, and of which 
we can form no conception, in creatures so far below us in the 
scale of organisation. 
I might here end my remarks on this insect, and in truth there 
is nothing more to be said about it. But, perhaps, it may add 
to the interest of this afternoon’s meeting if I briefly notice a few 
other cases of variation of structure, sometimes of instincts also, 
in different animals, one or two (as regards structure) bearing 
a close analogy to the case of the insect before us with its 
abnormally long antenne. . 
And here I may well adduce, in the first instance, the Long- 
armed Ape, or Gibbon (Hylobates uagilis), resembling in this 
respect the Cerambyx longimanus. This species is one of the 
Anthropoid Apes—so called from their nearer approach to man in 
form and structure than any other species of the monkey tribe. 
Its very remarkable arms are so long that the animal can touch 
the ground with its hands when standing erect. It is found in 
