Having recently come into possession of Leon de Rosny's late work entitled "_Les Documents ecrits de l'Antiquite Americaine_,"[1] I find in it a photo-lithographic copy of two plates (or rather one plate, for the two are but parts of one) of the Maya Manuscript known as the _Codex Cortesianus_. This plate (I shall speak of the two as one) is of so much importance in the study of the Central American symbols and calendar systems that I deem it worthy of special notice; more particularly so as it furnishes a connecting link between the Maya and Mexican symbols and calendars. This plate (Nos. 8 and 9 in Rosny's work), is entitled by Rosny "_Tableau des Bacab_" or "Plate of the Bacabs," he supposing it to be a representation of the gods of the four cardinal points, an opinion I believe to be well founded. As will be seen by reference to our Plate No. 1, which is an exact copy from Rosny's work, this page consists of three divisions: _First_, an inner quadrilateral space, in which there are a kind of cross or sacred tree; two sitting figures, one of which is a female, and six characters. _Second_, a narrow space or belt forming a border to the inner area, from which it is separated by a single line; it is separated from the outer space by a double line. This space contains the characters for the twenty days of the Maya month, but not arranged in consecutive order. _Third_, an outer and larger space containing several figures and numerous characters, the latter chiefly those representing the Maya days. This area consists of two distinct parts, one part containing day characters, grouped together at the four corners, and connected by rows of dots running from one group to the other along the outer border; the other part consisting of four groups of figures, one group opposite each of the four sides. In each of the four compartments containing these last-mentioned groups, there is one of the four characters shown in Fig. 1 (_a_ _b_ _c_ _d_), which, in my "Study of the Manuscript Troano," I have concluded represent the four cardinal points, a conclusion also reached independently by Rosny and Schultz Sellack.[TN-1] Before entering upon the discussion of this plate I will insert here Rosny's comment, that the reader may have an opportunity of comparing his view of its signification with the opinion I shall advance.