Whip spiders, or amblypygids, are arachnids, but only six of their eight legs are for walking. The front two are elongated sensory structures that process, among other things, smells. Whip spiders use these sensory legs to sniff their way back home after a night of hunting.

Read all about it in my latest Animal Minds post: The Arachnid That Smells With Its Legs