OLFACTOEY ORGANS OF WASP. 



55 



in fact, a fine hair, inverted over one of the usual 

 pits. 



In 1880 Hauser published an excellent memoir * 

 on the olfactory organs of insects, from which I have 

 taken Fig. 42, representing a section through part 



Fig. 42. — Section througn part of the antenna of a wasp (after Hauser), x 430. 

 Cff, Cbitinous sftin; Z, olfactory cone; (?, olfactory pit; TB, tactile hairs; U, 

 hypodermic cells; M, the membrane surrounding them; K^ nuclei of the olfac- 

 tory cells ; K,^ remains of the earlier upper nucleus ; SK^ lower circle of rods ; 

 US, olfactory rod ; GZ, Geisselzelle ; MZ, membrane forming cell ; J/, membrane 

 closing the pit. 



of the antenna of a wasp, showing two of the 

 olfactory cones, one projecting beyond the general 

 surface. They terminate above in a fine rod, below in 

 a nerve-thread, and present a double series of ridges. 



* "Phys. und Hist. Unt. ii. die Geruchsorgane der Insekten, 

 /«»■ Wise. Zool, 1880. 



' Zeit. 



