DISAPPOINTING news if you're a shareholder of Zeneca, the former ICI drugs arm. You may not have realised it, but you helped finance an entomological expedition to St Helena in the South Atlantic in search of the elusive giant earwig (L. herculeana). Alas, the bug- hunters recently returned empty-handed. It seems likely the species is extinct. Nothing has been sighted since 1988, when a previous expedition from London Zoo came across a tantalising pair of earwig pincers.