Most muskrats resemble house rats in appearance, but are significantly larger, their bodies reaching lengths as great as 14 inches. Also, their tails, which may grow up to 10 inches long, are flattened in a vertical direction and their powerful hind feet that help smoothly propel them through the water are partially webbed. Muskrats are generally solitary animals that live alone in burrows or lodgings composed of reeds or other marsh vegetation. They mark these domiciles and surrounding landmarks as components of their home territory by excreting a yellowish, pungent substance produced by the musk glands. This substance is sometimes utilized in the perfume industry.