Insects breathe through their bellies.
Humans and animals breathe through their nostrils and through their mouths. Fish breathe through their gills, which are just behind their heads. Insects need to breathe also but they do so through spiracles, little openings along the chest and belly (known as the thorax and abdomen). One insect, the water scorpion, has a breathing tube at the end of its abdomen, which it can push up to the surface of the water, rather like the snorkel of an underwater swimmer.