We have already noted some rather surprising preliminaries or accompaniments to insect coitus, but the mechanics of the coital act itself is sometimes equally remarkable. In bed bug copulation the sperm is placed in a pocket in the cuticle on the ventral surface of the female abdomen, whereupon the sperm actually makes its way through the body wall and reaches the ovaries via the blood stream. In many species - some bed bugs (as well as leeches, planarians, etc.) - the penis actually penetrates the body wall, resulting in a form of hypodermic insemination.