North American beaver large, webbed hind feet. The unwebbed front paws are smaller, with claws. The eyes are covered by a nictitating membrane which allows the beaver to see under water. The nostrils and ears are sealed while submerged. A thick layer of fat under its skin insulates the beaver from its coldwater environment. The beaver's fur consists of long, coarse outer hairs and short, fine inner hairs (see Double coat). The fur has a range of colors, but usually is dark brown. Scent glands near the genitals secrete an oily substance known as castoreum, which the beaver uses to waterproof its fur.
Castor and Pollux revered by the Romans, probably as the result of cultural transmission via the Greek colonies of Magna Graecia in southern Italy. An archaic Latin inscription of the sixth or fifth century BC found at Lavinium, which reads "Castorei Podlouqueique qurois" ("To Castor and Pollux, the Dioskouroi"), suggests a direct transmission from the Greeks; the word "qurois" is virtually a transliteration of the Greek word "κούροις", while "Podlouquei" is effectively a transliteration of the Greek "Πολυδεύκης". The construction of the Temple of Castor and Pollux, located in the Roman Forum at the heart of their city, was undertaken to fulfil a