This ‘black snake’ climbs trees with ease, and hangs from a branch to reach a nest below him. ‘He is the nimblest creature living,’ says an old writer on Virginia, for he not only has the credit of stealing hens’ eggs, but he ‘even swallows the eggs of small birds, without breaking them,’ which again is a proof of the remarkable control these creatures possess of regulating the pressure of their powerful jaws. Many of the African snakes climb trees, and also suspend themselves from a branch while reaching into a bird’s nest lower down for the eggs it may contain. Both Livingstone and Dr. Andrew Smith[10] make particular mention of some of the egg-eating snakes of South Africa, the latter in his general description of ophidians stating that ‘many, perhaps all snakes, devour eggs when they have an opportunity. A few feed entirely on eggs,’ notably some of the small tree snakes, to which the name _Oligodon_ (few teeth) has been given, this family having no teeth on the palate, like all other snakes. Their food, therefore, cannot be of a nature to require a very strong grasp, though we have no authority for stating that the _Oligodons_ feed exclusively on eggs. There is, however, one of the family with a dentition so remarkable that it has been considered a distinct type, and Dr. Andrew Smith, who was the first to observe its habits, gave it the generic name of _Anodon_ (toothless), the jaws being merely roughened with the rudiments of teeth. This little snake, of about two feet in length, is exclusively an egg-feeder. ‘Its business,’ says Professor Owen in his _Odontography_, ‘is to restrain the undue increase of small birds by devouring their eggs.’ Its remarkable organization is favourable for the passage of these thin-shelled eggs unbroken until far back in the throat or gullet, when the egg comes in contact with certain ‘gular teeth,’ which then break the shell without any loss of the contents to the feeder. These gular teeth are a curious modification of some of the spinal processes, presenting a singular anomaly in the presence of points of enamel on the extremity of some of them. Professor Owen has very fully described this remarkable development,[11] and as his works have been the text-books of many later physiologists, his words may here be quoted, even at the risk of repetition. ‘In the rough tree snake, _Deirodon scaber_, with 256 vertebræ, a hypapophysis—from ὑπὸ (Latin, _sub_), an offshoot from beneath—projects from the 32 anterior ones, which are directed backwards in the first ten, and incline forwards in the last ten, where they are unusually long, and tipped with a layer of hard cement (dentine). These perforate the dorsal parietes of the œsophagus, and serve as teeth.