Parrotfish make themselves a kind of mucus 'sleeping bag' which masks their smell from predators and keeps parasites away.
4
A scorpion can hold its breath for up to 6 days.
19
A cat rubs against people not only to be affectionate but also to mark out its territory with scent glands around its face. The tail area and paws also carry the cat's scent.
293
Penguins have a gland above their eye that turns saltwater into freshwater.
12