Page 11, reverse, from Codex Magliabechiano, showing the first four day-symbols of the <i><a href="https://en.wikipedia.org/wiki/en:tonalpohualli" class="extiw" title="w:en:tonalpohualli">tonalpohualli</a></i>: Flint, Rain, Flower, Crocodile.  Note how closely the Rain day-symbol resembles that of <a href="//commons.wikimedia.org/wiki/File:Tlaloc,_Codex_Rios,_p.20r.JPG" title="File:Tlaloc, Codex Rios, p.20r.JPG">Tlaloc</a>.
Unknown author<span style="display: none;">Unknown author</span>
mid-16th century
Codex Magliabechiano