Cockroaches, which hide in small cracks or crevices during the daytime,can reach lengths of 18 to 60 mm depending on species. They feed omnivorously on various organic substa- nces, including tissue, leather and paper. Cockroaches like e.g. the Oriental Cockroach (Blatta orientalis) and America n Cockroach (Periplaneta americana) occur throughout the world, especially in tropical regions where the environment is humid and warm.