Fig. 3. Life cycle of barnacles and the times when eicosanoids are thought to play a role in development (red boxes). Following fertilisation the eggs are brooded in the mantle cavity where hatching is under the control of hatching factors. The resulting planktonic larval stages undergo several moults until giving rise to the cyprid stage that uses its antennules to probe for suitable settlement sites. At settlement, these moult to give rise to juveniles (spat) that also grow and moult to give rise to a filter-feeding sedentary adult.