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Antenna of Insects. 
it has been found by the venerable physiologist Blumenbach * 
that these are the tribes which have the greatest developement of 
the organ. It is the same with quadrupeds : the animals which 
subsist on fetid substances, or which trace their prey from the 
greatest distance, are those in which the mucous membrane has 
the greatest extent of surface ; and Scarpa asserts that experi- 
ments on living birds have convinced him that the sense of smell 
is strongest in those which have the olfactory nerve the largest. 
The same is the case with fishes ; the shark, which is noted for 
acuteness of smell, has a nervous trunk under the principal fold 
of the mucous membrane, and also branches in the lateral folds, 
from which proceed filaments that penetrate and are regularly 
distributed through the substance of the membrane. From all 
this it seems to be clearly inferred, that in articulated animals the 
organ of smell is to be sought for in the existence of a part analogous 
in structure to the mucous membrane of the nose in vertebrated. 
Now to what extent does the general structure of the antennae 
seem fitted to exercise the faculty of smelling? Since in no in- 
stance with which I am acquainted are the antennae found to be 
lubricated with mucus exposed to the action of the atmosphere, 
and in only one or two cases are they perforated so as at all to 
resemble the olfactory organs of other animals, I am inclined to 
think that the more simple structures, the setaceous and filiform, 
would be best adapted for the olfactory sense, if indeed it resides 
in the antennae. 
Among those who believe that these are the olfactory organs 
is the celebrated Latreille.'j' He observes that the different species 
of beetles, Dcrmestes, Sylphce, Cleri, and Tenebr tones, perceive at 
a very considerable distance the smell of dead bodies and decay- 
ing substances, to which they resort to deposit their eggs ; that 
such is the case with many species of Diptera ; that the common 
blue flesh-fly, deceived by the odour of a species of Arum (the 
carrion-flower), alights on it, and deposits its eggs ; and that all 
these species are distinguished by a greater developement of the 
antennae than those of dissimilar habits. He observes also that 
many male insects have the antennae much larger than their 
females, and this he thinks may be easily explained if we suppose 
these parts to be the seat of smell. Bonnet appears also to be of 
a similar opinion. 
Huber, in his admirable work on Bees, conjectures that the an- 
tennae are the organs either of touch or smell, but does not state 
* Blumenbach’s Physiology, by Elliotson. Second edition, 1817, p. 141. 
f Samouelle’s Entomologist's Compendv 1819, p. 26. 
VOL. II. 
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