Banana slug, Ariolimax columbiana. Named for its yellow color which is similar to a banana. They can also be green, tan or spotted. The banana slug is the second-largest species of terrestrial slug in the world, growing up to 25 cm (9.8 in) long. Slugs use two pairs of tentacles to sense their environment. The larger, upper pair, termed "eyestalks," is used to detect light or movement. The second, lower pair is used to detect chemicals. The tentacles can retract and extend themselves to avoid damage. It inhabits the coniferous rainforest belt from se Alaska south to central CA. Photographed in Hoh rainforest, Olympic National Park, WA