The already sufficiently intricate ethnobotanical problem of peyote has been further complicated by an erroneous identification of a narcotic mushroom used by the Aztecs with the cactus peyotl. Safford[1] identifies the two by a somewhat casual use of his evidence, and mystifies himself with the consistent contradiction offered by all the early Spanish writers to his assumption. He composes the contradiction by assuming that the Aztecs did not recognize the dried discoidal button as the same plant as the green cactus; despite overwhelming etymological evidence he supposes they called the former teo-nanacatl and the latter peyotl. Only a complete review of the evidence can clear up this misapprehension. The Spanish writers consistently describe the two separately, with detailed circumstantial distinctions which leave no room for misunderstanding. Sahagún,[2] says [The Chichimeca] had a great knowledge of herbs and roots and knew their qualities and their virtues. They themselves discovered and first used the root that they call peiotl and those that used to gather and eat them used them in place of wine, and they did the same with those that they call nanacatl, which are toadstools [hongos malos] that also make one drunk like wine. Again, in a special chapter on intoxicating plants, Sahagún distinguishes the two: There is another herb like tunas of the earth [the Spanish name for the fruit of the prickly pear, _Opuntia opuntia_] which is called peiotl. It is white. It grows in the northern part. Those that eat it see frightening and laughable visions. This intoxication lasts two or three days and then stops....[3] There are some little mushrooms in their land that they call teo-nanacatl. They grow under the grass of the fields or pastures. They are round. They have a sort of high stem [pie], thin and round. They are eaten with great relish, but they harm the throat and make one drunk.[4] Still further to emphasize the point, Sahagún in the next section of this chapter[5] goes on to speak of edible mushrooms: The cone-shaped mushrooms (mushrooms or nanacatl) _genus campos agrorum_ in the mountains are good to eat. They are cooked because of this, and if they are raw or badly cooked, they produce vomiting or diarrhea, and they kill one, and he continues to list and describe a number of other edibles. The naturalist Hernandez[6] is even more explicit. He describes teo-nanacatl under the heading “De nanacatl seu Fungorum genere”; and from the harmless white mushrooms, iztacnanacame, the red mushrooms, tlapalnanacame, and the yellow-orbicular mushrooms, chimalnanacame, he distinguishes teo-nanacatl as “teyhuinti,” that is, “intoxicating.” Siméon’s Nahuatl dictionary even uses nanacatl as an illustration:[7]