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Mr. G. Newport on the 
supplied with medullary matter from the very brain itself, we 
should naturally conclude that they must be of almost vital im- 
portance to the insect, or that the excision of even a portion would 
at least deprive the insect of its usual faculties. But this, experi- 
ments have amply proved is not the case. Every one who has 
been in tbe habit of collecting specimens for his cabinet must have 
remarked how frequently he has met with such as have had one 
of the antennae mutilated, or perhaps have been wholly deprived 
of it, yet the instincts of the little creatures have not appeared to 
suffer, nor would their existence, probably, have been shortened in 
the slightest degree by the loss. Yet are these organs regarded 
with the utmost solicitude by their possessors, and are imme- 
diately withdrawn when they happen accidentally to have come in 
contact with any substance, which at once proves their great sus- 
ceptibility of feeling as well as the solicitude of the insect for their 
preservation. Of what utility then are they to the insect ? Are 
they for the purpose of smelling, touching, or hearing? Upon 
this question the greatest naturalists are undecided, some con- 
tending for one sense, some for another, and all supporting their 
opinions by experiments and plausible reasoning ; nor is this di- 
versity of opinion to be wondered at, when the various structures 
of the organs themselves and the modes in which they are used 
by different insects are considered. The only method by which 
we can arrive at a certain conclusion is by connecting experi- 
mental observations on the manner in which the antennae are used 
by different insects, with remarks on their anatomical structure, 
and, comparing these, to observe how far they coincide so as to 
be universally applicable to the whole class, and to indicate the 
possession of the sense of smelling, touching, or hearing. 
First, in our inquiry as to the probability of their use as organs 
of smell, we may premise, that in vertebrated animals, from man 
to the reptile, the organ of this sense is situated in the face or an- 
terior part of the head ; it consists of two or more apertures, the 
interior of which is of the most delicate structure, being furnished 
with small blood-vessels distributed over the whole surface, and 
anastomosing in minute glands, which secrete a thick mucus. This 
mucus is diffused all over the membrane, and the olfactory nerves 
ramify beneath it. It seems to be that the perfection of the sense 
depends in a great measure on the magnitude of the organ and 
its nerves, and the extent of surface acted on and properly sup- 
plied with mucus. Thus in the human species it has been often 
remarked by travellers that many of the savage tribes of Africa 
are distinguished for a very extraordinary acuteness of smell, and 
