On the well-known bas-relief preserved in the National Museum of Mexico, and illustrated in the Anales (vol. I, p. 63), the two historical rulers of ancient Mexico, who figure as Quequetzalcoas, or divine twins, in exactly the same costume, are sculptured with blood flowing from their shins and in the act of piercing their ears with a sharp bone instrument. Two streams of blood descend from these and meet before falling into the open jaws figured beneath an altar, on which two conventionalized flowers appear. The two rows of teeth=tlantli, convey the sound of the affix tlan=land of, or tlalli=earth. But the most remarkable and striking instance of the group of ideas we have been studying is found on p. 62 of the Borgian Codex. On a background formed by a pool of water, there is a group which represents the “earth-mother” lying on a band of lizard-skin, with two maize plants issuing from her body and growing into a large two-branched tree, in the centre of which is a flint-knife or tecpatl. A bird stands on its summit and its branches terminate in maize plants. Its growth is being furthered by the two streams of blood which proceed from two human figures, standing at each side of the tree. One is painted black and evidently represents the Lord of the Below; the other is painted blue-green and represents the Lord of the Above. The blood-sacrifice they are jointly offering is that mentioned in the “Lyfe of the Indians,” as performed in order to obtain generation. Unquestionably this symbolical group would have been equally intelligible to Mayas or Mexicans, since the ideas it expressed were held in common by both people.