NO. 9 OLFACTORY SENSE OF INSECTS AJcTNDOO 7 



"INTERNAL SUPERIOR SUREACE" AS SEAT OE OLFACTORY 



ORGANS 



After discussing" the various views concerning the location of the 

 organs of smell, Ikirmeister (1836) concludes as follows: 



Thus insects, according to my opinion, would smell with the internal superior 

 surface, if I may so call it, which is provided all over with ramifications and 

 nets of nerves, since this is always kept moist by the blood distributed through 

 the body and by transpired chyle, tlie same as is surmised of the superior Mol- 

 lusca. 



I'urlher, the same authorit}- wrote. 



Various authors consider the antennje as olfactory organs, but with what 

 right? A hard, horny organ, displaying no nerve upon its surface, can not 

 possibly be the instrument of smell, for we always find in the olfactory organ 

 a soft, moist, mucous membrane, furnished with numerous nerves. 



What Burmeister means by " internal superior surface " is not 

 clear. 



DIEEERENT PARTS AS SEAT OF OLFACTORY ORGANS 



Schelver (1798), cited from Lacordaire (1838), and Comparetti 

 (1800), according to Perris (1850), place the seat of smell in differ- 

 ent parts for different families, as follows: The club of the antennas 

 in lamellicorns, the proboscis in the Lepidoptera, and certain frontal 

 cells, which have never been seen since by any one else, in the 

 Orthoptera. 



FOLDED SKIN BENEATH ANTENN.^ AS SEAT OF OLFACTORY 



ORGANS 



Rosenthal (1811), cited by Ikirmeister (1836), "described a 

 folded skin at the forehead, beneath the antennae, to which two fine 

 nerves passed, and which he considers the organ of smell in the flies 

 Musca domestica and (Mnsca) Calliphora vomitoria; and he ob- 

 served, after the destruction of the part, a deficiency of the function 

 which had previously strongly exhibited itself." 



The honey bee has no such structure as that described by Rosenthal. 



RHINARIUM AS SEAT OF OLFACTORY ORGANS 



Kirby and Spence (1826) regard the rhinarium as the location of 

 the organs of smell. The rhinar.ium or nostril-piece is the foremost 

 portion of the clypeus just above the labrum; it consists of circular 

 pulpy cushions, covered by a membrane transversely marked with 

 fine striae. These fleshy cushions, like the upper surface of the 

 tongue, are beset with minute black tubercles carrying bristles. 



No such structure as the rhinarium exists in the bee. 



