ABSTRACT
Many glands are common to all social insects and occur in the queens, workers and males, as is for example the case for the mandibular and salivary glands. The number of known exocrine glands in social insects becomes more and more impressive, and reflects the evolution of sectioning techniques. Glands are structures specialized for the storage and the emission, spreading or evaporation of their secretory products. The exocrine system in social insects is extremely well developed. Pheromone producing glands are distributed over all regions of the social insect's body, with a location that is directly linked with their function. The use of trail pheromones represents a commonly known communication system for terrestrial social insects like ants and termites. By far the best understood of the sexual pheromones of social insects is the queen substance of honeybees. There are territorial social insects that defend a territory marked with their glandular secretions.
