184- ANATOMY AND PHYSIOLOGY 



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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 perform- 

 ed ; and there is scarcely any part of the body to 

 which the olefactory perceptions have not been 

 assigned by different physiologists. Lyonnet, Bons- 

 dorf, and Marcel de Serres, considered the palpi as 

 the organs of smell ; Camparetti, various appendages 

 of the head ; Kosenthal and Robineau Desvoidy, a 

 small vesicular membrane, between the antennae of 

 the Muscidse ; 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 mar- 

 ginalis, and they suppose similar parts to exist in 

 other insects. But M. Treviranus, and other anato- 

 mists, have been unable to discover them, and there 

 can be no doubt that the Fathers of British Entomo- 

 logy 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 ver- 

 tebrata, is closely connected with the act of respira- 



