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184 tip of the proboscis, which is commonly provided with glandular points. The sense of smell, or at least some power which communicates analogous intimations to the sensorium, is in a high state of perfection; for the distance from which insects are attracted by the fetor of some choice pabulum, or the scent of some favourite flower, (such as the catkins of the willow in early spring,) is truly astonishing. Yet nothing is more uncertain than the organs by which this service is so admirably performed; and there is scarcely any part of the body to which the olefactory perceptions have not been assigned by different physiologists. Lyonnet, Bonsdorf, and Marcel de Serres, considered the palpi as the organs of smell; Camparetti, various appendages of the head; Rosenthal and Robineau Desvoidy, a small vesicular membrane, between the antennæ of the Muscidæ; and Kirby and Spence, the rhinarium or nostril-piece. The last named authors detected a pair of spongy bodies under the tegument of the part so named in Necrophorus Vespillo and Dytiscus marginalis, and they suppose similar parts to exist in other insects. But M. Treviranus, and other anatomists, have been unable to discover them, and there can be no doubt that the Fathers of British Entomology have, in this rare instance, fallen into error, or at least assigned too much importance to a variable, evanescent, and non-essential part of structure.

From the consideration that this sense, in the vertebrata, is closely connected with the act of