The structure and distribution of nasal glands in four marsupial species.

The structure and distribution of nasal glands in four marsupial species were studied by light and electron microscopy. The species studied were the honey possum (Tarsipes rostratus), the bandicoot (Isoodon macrourus), the koala (Phascolarctos cinereus) and the agile wallaby (Macropus agilis). Glands were grouped and described according to their location. Those of general distribution (goblet cells and olfactory glands) were similar in structures and distribution in all specimens. Glands of the lateral nasal wall include the lateral nasal, maxillary sinus and turbinate glands. The lateral nasal and maxillary sinus glands were absent in the adult koala but occupied large areas in the other species. Turbinate glands were best developed rostrally and ventrally in the nasal cavity. On the nasal septum, Tarsipes and Isoodon had well developed glands associated with vascular 'swell bodies'. These were poorly developed to Macropus though septal glands were abundant. 'Swell bodies' were absent in Phascolarctos and glands were sparse. Tubular vomeronasal glands were present in all species and most extensive in Tarsipes. In Isoodon, there was a posterior ventral septal gland associated with the septal olfactory organ. The fine structural features of secretory cells and ducts are described and their potential role discussed in terms of chemoreception and temperature and humidity control.