The Tzental and Quiche-Cakchiquel, _tziquin_, signifies "bird" in general, and the Nahuatl, _quauhtli_, "eagle." The Maya and Zapotec names are more difficult to bring into harmony with the others. Dr Brinton thinks that the Zapotec name is derived from _na_, "to know, to understand, to be able through knowledge." This, he says, "exactly corresponds to the Maya _men_, which means to understand, to be able to do ...; hence in this latter tongue, _ah-men_ means the man of knowledge, the wise one, the master of wisdom." "The bird," he adds, "was the symbol of wisdom and knowledge." Dr Seler says it is difficult to determine the Yucatan name. However, from the form of the symbol he concludes it is intended to represent an aged face, by which he connects it with an aged goddess, Ixchel, the companion of Itzamna, and with certain Mexican deities. In his subsequent paper he says the Zapotec name furnishes linguistic proof of the above conclusion. "I had concluded," he says, "that the Maya hieroglyph represented the image of the old earth mother, the universally worshipped goddess called Tonantzin, 'our mother,' who is connected in the Codex Vienensis with the eagle symbol." He then adds that the Zapotec term _naa_ or _ñaa_ signifies "mother," and thus finds the connection between the calendar names. It is probable we will not be far wrong if we assume that reference to the bird as used in this connection is not so much to it as an animal as an augury, sign, or portent. The birds introduced in the Dresden and Troano codices, especially those on pages 16, 17, and 18 of the former and 18* and 19* of the latter, are supposed to have reference to auguries. In the "Vocabulario Castellano Zapoteco," under "Ave," we find _mani-biici_, "ave agorera." In the Dresden Codex (17b) one of the birds introduced as playing this rôle is an eagle, or some rapacious species resembling an eagle or vulture. Although Seler believes the symbol to have been derived from the aged wrinkled female face, yet he closes his observations on this day in his first article as follows: I think the reference to the eagle is very distinctly indicated [referring to a number of glyphs accompanying or indicating an eagle-like bird]. We can understand that these hieroglyphs were annexed as attributes of the deities. But how is it that figures 687-689 [same as our plate LXVIII, 42] serve as a seat for the Chac? Now Chac [he refers to the long-nose god] is not really a god of water, but of rain; the rain-producing storm cloud is his vehicle; the storm bird is his beast of burden on which he rides. It follows from this, notwithstanding his supposition in regard to the origin of the symbol, that he looks upon it as signifying the eagle, or bird. However, the explanations given by Drs Brinton and Seler of the Maya name fail to make a satisfactory connection between the names in the different calendars.