36 DIFFERENT THEORIES AS TO 



In insects the separation of the mouth from the 

 respiratory orifices is, in this respect, a manifest dis- 

 advantage. Still, it was not unnatural to look for the 

 organ of smell in the neighbourhood of the spiracles, 

 Sulzer's view was supported by Von Keimarus, Baster, 

 Dumeril, Schelvir, and especially by Lehmann,* who 

 lays it down as a general proposition that every organ of 

 smell is to be sought near the orifices through which 

 animals breathe : " Omnibus olfactus organon in iis 

 locis quserendum est, per quos inspirent." 



The most careful observations, however, have failed 

 to detect in the neighbourhood of the spiracles any 

 special supply of nerves, or any organ which could be 

 supposed to serve for the perception of odors, and I 

 believe this view may be said to be now generally 

 abandoned.! 



Treviranus J suggested that the organ of smell was 

 situated in the mouth, and he has been followed by 

 Newport, Wolff, Kirby and Spence, and Graber. The 

 descriptions they have given may be accepted as 

 correct, but the organs they describe in the mouth 

 itself are rather, I think, to be ascribed to the sense 

 of taste than to that of smell. 



Lyonnet, Bonsdorff, Marcel de Serres, Newport, and 

 others, believed that the sense of smell resides in the 



* Lehmann published three memoirs on the subject : " De Sensibus 

 Externis Animalium Exsanguium," 1798 ; " De Antennis lusectorum 

 Dissertatio," 1799; and "De Antennis Insectorum Dissertatio PoS' 

 terior," 1800. 



t Joseph, indeed (" Bericht der 50 Vers. Deutscher Nat. und Aerzte. 

 Miiuchen," 1877), supported this view in a short communication, and 

 has promised fuller details. These, however, have not, I believe, yet 

 appeared. 



X " Ueber das Saugen und das Geruchsorgan der Insekten," Ann. 

 der Wetter Qes., 1812. 



