Myrmekite-like intergrowths in the Lewisian gneiss and the igneous complex of Loch Borolan are described. The intergrowths are of diverse mineral composition but have many features in common with myrmekite and it is shown that they result from the constriction of a previously existing mineral during the growth, in the solid state, of the host mineral. More than one stage of intergrowth is often found and these stages can be correlated with geological events.