Mark N Hutchinson
Articles written in Journal of Biosciences
Volume 25 Issue 2 June 2000 pp 173-179 Articles
The luminal surface of the chemosensory epithelia of the main olfactory organ of terrestrial vertebrates is covered by a layer of fluid. The source of this fluid layer varies among vertebrates. Little is known regarding the relative development of the sources of fluid (sustentacular cells and Bowman’s glands) in reptiles, especially in gekkotan lizards (despite recent assertions of olfactory speciality). This study examined the extent and morphology of the main olfactory organ in several Australian squamate reptiles, including three species of gekkotans, two species of skinks and one snake species. The olfactory mucosa of two gekkotan species (
Volume 25 Issue 2 June 2000 pp 181-190 Articles
The vomeronasal organ is a poorly understood accessory olfactory organ, present in many tetrapods. In mammals, amphibians and lepidosaurian reptiles, it is an encapsulated structure with a central, fluid-filled lumen. The morphology of the lubricatory system of the vomeronasal organ (the source of this fluid) varies among classes, being either intrinsic (mammalian and caecilian amphibian vomeronasal glands) or extrinsic (anuran and urodele nasal glands). In the few squamate reptiles thus far examined, there are no submucosal vomeronasal glands. In this study, we examined the vomeronasal organs of several species of Australian squamates using histological, histochemical and ultrastructural techniques, with the goal of determining the morphology of the lubricatory system in the vomeronasal organ. Histochemically, the fluid within the vomeronasal organ of all squamates is mucoserous, though it is uncertain whether mucous and serous constituents constitute separate components. The vomeronasal organ produces few secretory granules intrinsically, implying an extrinsic source for the luminal fluid. Of three possible candidates, the Harderian gland is the most likely extrinsic source of this secretion.