As the evolution of religious thought and symbolism progressed, this idea would obviously lead to the conception of a single being uniting several natures in his person. In this connection it is certainly extremely interesting to find the serpent associated with the Calendar in Mexico and Yucatan, its Nahuatl name being homonymous for twin, _i. e._ two, and the Maya for serpent, _can_ or _cam_, being homonymous for the number four. The serpent was, therefore, in both countries the most suggestive and appropriate symbol which could possibly have been employed in pictography, to convey the idea of dual or quadruple natures embodied in a single figure.(3) Added to this the circumstance that, to the native mind, the serpent, upon merely shedding its skin, lived again, we can understand why the ancient Mexicans not only employed it as a symbol of an eternal renewal or continuation of time and of life, but also combined it with the idea of fecundity and reproductiveness. In Yucatan where the Maya for serpent, _can_, is almost homonymous with _caan_=sky or heaven and the adjective _caanlil_=celestial, divine, the idea of a divine or celestial serpent would naturally suggest itself. It is therefore not surprising to find, in both countries, the name of _serpent_ bestowed as a title upon a supreme, celestial embodiment of the forces of nature and its image employed to express this association in objective form. In Yucatan one of the surnames of Itzamná, the supreme divinity, was Canil, a name clearly related to _caanlil_=divine and _can_=serpent. In Mexico the duality and generative force implied by the word “coatl” are clearly recognizable in the native invocations addressed to “Our lord Quetzalcoatl the Creator and Maker or Former, who dwells in heaven and is the lord of the earth [Tlaltecuhtli]; who is our celestial father and mother, great lord and great lady, whose title is Ome-Tecuhtli [literally, two-lord=twin lord] and Ome-Cihuatl [literally, two-lady=twin lady”] (Sahagun, book VI, chaps. 25, 32 and 34). The following data will suffice to render it quite clear that the Mexicans and Mayas employed the serpent as an expressive symbol merely, signifying the generative force of the Creator to whom alone they rendered homage. It is no less an authority than Friar Bartholomew de las Casas who maintained that “in many parts of the [American] Continent, the natives had a particular knowledge of the true God; they believed that He created the Universe and was its Lord and governed it. And it was to Him they addressed their sacrifices, their cult and homage, in their necessities...” (Historia Apologetica, chap. 121).