American students of ancient Mexico and Central America have almost entirely confined themselves to the examination of sites and monuments. In France, M. Beuchat has provided students with an admirable handbook in his Archéologie Américaine, which, if too general in its purport and marred by a lack of linguistic knowledge, is still valuable as an elementary manual to American antiquity. The essays of Lehmann, De Jonghe, and Preuss have provided the student with translations of manuscript material hitherto closed to him, or have smoothed his way to a clearer comprehension of the difficulties connected with the Mexican calendar. The best modern English handbook on Mexican archæology is that by Mr. T. Athol Joyce, of the British Museum, but its lack of references is a serious drawback and the material it contains suffers from compression. The method of my investigation of the divine forms of Mexico is set forth in the introductory paragraph immediately preceding that part of the book which deals with the gods more especially. Regarding the tonalamatl and the Calendar, I have thought it best to relegate this difficult and obscure subject to an appendix, in order that it should not interfere with the main current of proof. In dealing with the Codices throughout I have employed the pagination of Seler rather than that of Kingsborough, as referring to the more modern and greatly preferable editions of the Duc de Loubat, except in cases where a manuscript is to be found in Kingsborough’s work alone. It is my sincere hope that the bibliography at the end of the book as well as that to be found at the conclusion of the appendix on the tonalamatl will lighten the labour of students of Mexican religion, whose co-operation in the discovery of errors I most cordially invite. The illustrations in this book are, for the most part, taken from the native Mexican codices or paintings, and from representations of the gods in stone or pottery. It has, of course, been impossible to furnish every picture or representation alluded to in the text, but these, in their entirety, will be found in the excellent coloured reproductions in collotype published by the Duc de Loubat, full particulars of which are given in the bibliography of the codices on pages 378–381. These reproductions can be consulted in many of the greater libraries, especially in those connected with the Universities. I have preferred, in many cases, to furnish the student with those representations of the gods which he would have found it more or less difficult to procure. The numbers of the pages or sheets attached to the illustrations refer to the places where the respective figures can be found in the reproductions of the Duc de Loubat.