# Matlactli Omei Acatl (Mdz2r)

This combined simplex glyph and notation for the solar year (*xihuitl*) date, Thirteen Reed (*Matlactli Omei Acatl*), includes a notation for the number thirteen (*matlactli omei*), plus the calendrical representation of the reed/arrow (*acatl*). This representation of the reed has a short, upright reed decorated with feathers. The reed also stands in a small, symbolic *apantli* (waterway) in a cross-section view. The circles of the notation are grouped into two fives and one three. Each group of five starts at the top of the black-line box that contains the date and then runs down the sides. The group of three small circles are centered along the top of the box. The black-line box that encloses this date is not visible in this image. Also note how ones can sometimes have dots in the middle and sometimes concentric circles.

Stephanie Wood

The notation serves as something of a mathematical equation, 5 + 3 + 5 = 13. Sometimes the two fives are contiguous, but here they are separated by the three. The groupings of circles in these notations brings to mind the ancient way of counting on one's fingers (and possibly toes) along with a way of thinking about sums. For a different grouping of ones for totaling 13, see *Matlactli Omei Calli*, below. Another thing worth noting in the equation is the the plus signs (ligatures) are visually represented as spaces between groupings of ones. Finally, the turquoise blue (*xihuitl*) color is used as a clue that this is a year date (*xihuitl*), given that the two words are homophones. Calendrics were an important element in the Nahuas' religious views of the cosmos.

Stephanie Wood

c. 1541, or by 1553 at the latest

Stephanie Wood

dates, fechas, calendars, calendarios, números, cañas, carrizos, flechas, plantas, plumas, canales, xiuhpohualli, año, turquesa, xihuitl

*matlactl omei*, thirteen, https://nahuatl.wired-humanities.org/content/matlactli-omei

*aca(tl)*, reed, https://nahuatl.wired-humanities.org/content/acatl

Trece Caña

Stephanie Wood

Codex Mendoza, folio 02 recto, https://digital.bodleian.ox.ac.uk/objects/2fea788e-2aa2-4f08-b6d9-648c00..., image 14 of 188.

The Bodleian Libraries, University of Oxford, hold the original manuscript, the MS. Arch. Selden. A. 1. This image is published here under the UK Creative Commons, “Attribution-NonCommercial-ShareAlike 3.0 License” (CC-BY-NC-SA 3.0).