Another is the _Cylindrophis_, from its form. Several of the burrowing family are remarkable for a similarity of head and tail, obscure features, inconspicuous eyes, and very small mouth, rendering it difficult on first sight to decide which is the head and which the tail. All being feeble, inoffensive, and entirely harmless, the evil attached to them of having ‘two heads’ is only another proof of the prejudice and animosity displayed towards every creature in the shape of a snake, however innocent. These poor little ‘blindworms,’ admirably organized to dig and burrow and find their food in deep and hidden places, have their uses. In countries where dangerous ants swarm, we might well tremble for the consequences, had not nature anticipated such evils by providing insectivorous reptiles, as well as birds and ant-eaters, to keep them in check. We must not omit one other of the family of burrowing snakes, which from the very earliest ages has been supposititiously endowed with two heads. Its name, _Amphisbæna_, or ‘double-walker’ (going both ways), however, is well merited, because, like _Typhlops_, it can progress either way, forwards or backwards, with equal facility. This is the one alluded to by Catesby (p. 174). We can comprehend the advantage of the retrogressing power to these otherwise unprotected little reptiles, when they cautiously peep from their narrow burrow in the ground, and espy one of their many enemies in the shape of a much larger ophidian, or a carnivorous bird. Quick as thought, back they glide, and are safe. Living chiefly among the ants, on which they feed, their cuirass of hard, polished, close-set scales protects them from a bite or sting. Another beautiful provision of nature is, that the young ones, on being hatched, find food ready at hand—at mouth, rather—the eggs having been laid, or the young ones born, in the nest of the ants. Of this harmless and useful reptile, Pliny seriously wrote: ‘The amphisbæna has two heads; that is, it has a second one at its tail, as though one mouth were too little for the discharge of all its venom!’ Even at the present day this belief in ‘two heads,’ or ‘two tails,’ and ‘death at both ends,’ is not wholly eradicated, and not merely among the lower classes either. It only remains to say that when two heads have really appeared—and there are several such cases on record—they are simply monstrosities, malformations, as found in other animals occasionally. An example of this kind may be seen at the Museum of the Royal College of Surgeons. Another was described by Frank Buckland in _Land and Water_, April 1872. It was sent to him by his friend Dr. Bowerbank of St. Leonard’s.