BRITISH REPTILES
brane forming the " shell " can be cut through. The food consists of birds and eggs, frogs, insects, mice, newts, slugs, water-voles, and, it is said, fish. I have known one to consume a nest full of young nightingales which I had under observation. This species is much thinner in proportion to its length than the Adder, and tapers much more towards the extremity. This is not an invariable rule, but holds good in most cases. The general colouration is olive-green, with darker above, and greenish-yellow lower down. There is a conspicuous orange, or yellow, ring or collar, with a narrow line of dark colour on the back of the neck. Behind this there is a dark band, which is more pronounced on the neck-
sides than on the back. There is a single row of black markings on either side of the body. The young are darker at first, but soon assume the colouring of the parents. It attains a much greater length than the Adder, the average being between 30 and 36 inches. Larger specimens have been recorded, one of 5 feet 8 inches having been obtained in Hampshire, but this may be regarded as phenomenal. In addition to haunting marshy situations, this species is fond of entering water quite voluntarily, and propels itself along with its head just protruding from the liquid element. Its movements are graceful and well worth watching. As with all the reptiles, it casts its skin regularly, turning itself inside out as it were, head and eye-coverings included, and during Winter passes its time, Like its congeners, in a state of torpor. It makes a most interesting
