Published online by Cambridge University Press: 19 September 2011
The sternal gland shows significant differences in size and activity in different instars of the worker caste of Trinervitermes bettonianus. Gland size (volume and surface area) was not significantly different between instars 1 and 2, and 2 and 3; but was significantly different between these age groups and instars 4–7. The potential trail-laying activity of the gland of a worker increased from zero to 50 trail units in the course of development from the first to seventh instar. The relatively high biological activity of the gland in the older instars 5–7 may be of ecological significance, since these stages were found to constitute over 90% of foragers under field conditions.