Pacific banana slug

Ariolimax columbianus is the second largest land slug in the world. Adults range from 15-20cm in length. Some have been recorded at 25.4 cm! Augustus A. Gould first gave these soft bodied invertebrates a scientific name in 1851. Some of the first studies were conducted along the Columbia River; hence the species name A. columbianus (Harper 1988). Gastropoda describes the banana slugs stomach-foot or muscular-foot, which allows them to slowly crawl on a series of muscular waves (Denny 1980). Pulmonata describes their small lung that opens to the outside with a pneumostome, the hole slugs breathe through. The banana slug is the second largest slug in the world, growing up to 10 inches in length. On average they range between 6-8 inches, with a life span of 1-7 years (Harper 1988). Their coloring is sometimes bright yellow, occasionally with black spots, or solid greenish. Individual slugs will change colors with alterations in food consumption, light exposure, and moisture levels. Color may also indicate whether a slug is healthy, injured, or what age they are (Harper 1988). Their coloring allows them to camouflage with leaves and other debris on the forest floor. This serves as protection from such prey as beetles, raccoons, and even other banana slugs (Harper 1988). That’s right, these funny critters are tertiary consumers. They are forest floor scavengers that feed on small (already dead) animals, but they are mostly decomposers, feeding on detritus. Banana slugs are considered general herbivores that eat all kinds of leaf litter, green plants and fungus (mushrooms are their favorite foods) and occasionally feed on animal feces and carcass (Rollo 1983). In the process of debris munching, the A. columbianus disperse seeds and spores while excreting a nitrogen rich fertilizer (Gordon 1994). Slugs, at times are also frugivores and may play a minor role in forest plant regeneration and seed dispersal (Gervais 1996).
Source: http://online.sfsu.edu/bholzman/courses/Fall00Projects/bananaslug.html