136 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. 146 
^BOW [jOV /40Wr /2OW 
Fig. 18 — Major habitat zones in Latin America (after Piatt, 1942. fig. 
491). A broken line surrounds the portion of Mesoamerica where the earliest 
evidence of plant domestication has been found, and that part of Colombia pre- 
senting a similar combination of habitat zones. 
