Fig. 8.

Female and male antenna of Manduca and projections of olfactory receptor cells to the female antennal lobe. a Scanning electron micrograph of a portion of an adult female antennal flagellum showing several annuli. b Portion of an adult male antennal flagellum showing several annuli. c Higher magnification view of a single annulus from a female antenna. Long, hair-like sensory organs (trichoid sensilla) are abundant on the surface of an annulus. d, e Laser scanning confocal microscope images showing serial optical sections of specimens embedded in plastic and sectioned to improve resolution, taken at different depths through the female antennal lobe. Images show central projections of olfactory receptor cell axons stained with the fluorescent dye dextran-tetramethylrhodamine. Asterisks indicate the two sexually dimorphic large female glomeruli located in the dorsolateral region of the antennal lobe, near the site of entry of the antennal nerve (AN). The arrows indicate sexually isomorphic glomeruli. do dorsal, la lateral