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appears to approve the system of B aster and Dumeril respect- 
ing the position of the organs of smell in insects, says nothing 
particular with regard to the Crustacea. M. de Blainville, in 
his last work, adopts as most probable, the opinion that the 
antennae are the seat of smell in all the articulated animals, 
because it is in accordance with many considerations a priori. 
He thinks that in the invertebrated animals, the apparatus of 
olfaction presents this difference to what takes place in ver- 
tebrated animals : that the skin, more or less modified, no 
longer lines a cavity or pouch, lodged in the head ; but that 
it clothes the extremity of the appendages which may project 
more or less in front of the animal, such as the antenna) or 
tentacula. 
Of the four antennae, which exist in the Crustacea, M. de 
Blainville seems to think that the seat of smell resides rather 
in the two intermediate, than in the two exterior. 
There can be no sort of doubt that the sense of taste exists 
in the Crustacea, and it appears probable that its seat is 
placed at the commencement of the intestinal canal; for we 
find that some of the nervous threads which are furnished by 
the two cords surrounding the oesophagus, proceed to this 
part. Nevertheless, one might also suppose it to be in the 
flagelliform palpi, which are annexed to the back of the jaw- 
feet, just as it was, for a long time, admitted to exist in the 
maxillary and labial palpi of the insects ; but these palpi of 
the crustacea are by no means conformed for the perception 
of savours, and are not even organs of tact. They can be con- 
sidered as nothing but true appendages of locomotion, a little 
modified, and which can serve at most only to direct the prey 
towards the jaws. 
Touch would appear to be an extremely obtuse sense in the 
majority of the animals of this class. The very name of 
crustacea sufficiently indicates that their skin, the ordinary 
seat of this sense, is hardened, and changed into a truly solid 
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