Species of Tagetes are widely used in Mexico as me- 
dicinal plants and at times seem to carry some ceremonial 
significance (17, 164). The showy and variable 7°. erecta 
and 7". patula must, like the dahlia, have had a long his- 
tory of cultivation as ornamentals in Mexico. (17, 49, 
50, 98, 138%, 143, 164, 192) 
Taxodium mucronatum 7Ten.: Ahuéhuetl, ahue- 
huete, Mexican bald cypress. 
Though perhaps not properly listed as a cultivated 
plant, the noble ahuehuete surely deserves mention. It 
is known to have been planted by the ancient Mexican 
rulers in their parks and gardens, and a number of the 
trees thought to have been planted by Netzahualcéyotl 
and Moctezuma II are still living. A good account is 
given by Martinez. (135*, 191) 
Theobroma Cacao L.; T. angustifolium DC:: 
Cacao; T. bicolor Humb. & Bonpl.: Patachtli, pataxte. 
Cacao was highly valued in Mexico as the source of 
wocdatl, a drink somewhat different from the modern 
chocolate. The seeds were often used as a medium of 
exchange. 7 Cacao is a rather variable population and 
some authors have recognized several species on the basis 
of fruit shape and other characters. Cheesman (45) recog- 
nizes two main groups. The ‘‘Criollo’’ varieties, with 
plump seeds and pale or unpigmented cotyledons, pro- 
duce the highest quality of seeds, and are thought to be 
the original cacao varieties of Mexico and Central Amer- 
ica. ‘These are known to occur also in Colombia and 
Venezuela, but were apparently not cultivated there in 
pre-Columbian times. The ‘‘Trinitario’’ varieties (7°. 
leiocarpa Bernoulli), with flattened seeds and purple coty- 
ledons, have been brought into cultivation in relatively 
recent times from wild Amazonian trees. The early de- 
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