Date: 1870
This she accomplishes by means of her flat hind feet, and aster this manner : She digs up the sand with one foot, and throws it to one side.  Then she uses the other foot in the same manner, working with one foot after the other, alternately, like a machine , as Neu Wied has re marked.  * The sand which would be likely to fall back again is moved out of the way by the foot, which moves forward before it is thrust down to deepen the hole, and scrapes the sand to one side.