supply of coca leaves and cocaine. This species is native to the 
montana region of the eastern Andes, extending from Ecuador 
south to Bolivia. It is cultivated mostly between 500 and 1500 m. 
elevation in an area characterized by a favorable tropical envir- 
onment with high rainfall, moderate temperatures, and well 
drained, mineral-rich soils. 
A distinct variety of Erythroxylum Coca is also found in 
South America but has been largely ignored by both botanists 
and anthropologists. This is the coca of the Amazon valley, 
which continues to be cultivated today on a small scale by a 
number of Indian tribes in the western Amazon of Brazil, 
Colombia and Peru. The history, cultivation, method of use and 
alkaloid chemistry of Amazonian coca was discussed recently in 
a paper read before the 43rd International Congress of America- 
nists (Plowman, 1979b). 
Amazonian coca is readily distinguished from typical Ery- 
throxylum Coca (E. Coca var. Coca) of the Andean foothills. 
The Amazonian variety grows typically as a tall, spindly shrub 
with long, weak branches and relatively large, elliptical leaves. 
The leave are usually blunt or rounded at the apex in contrast to 
montana coca which usually has more or less pointed leaves. 
The parallel longitudinal lines found on the leaf undersides and 
usually considered characteristic of E. Coca are often faint or 
even lacking in the Amazonian variety. Furthermore, the flow- 
ers of Amazonian coca have a shorter, thicker pedicel and a 
markedly denticulate staminal tube. 
Erythroxylum Coca is a self-incompatible, distylous species 
with both long-styled (pin) and short-styled (thrum) morphs, 
which occur in approximately equal numbers (Plowman, unpub- 
lished data; Ganders, 1979). However, most populations of 
Amazonian coca contain only the short-styled morphs, with the 
exception of one or two collections from the easternmost 
Amazon in Brazil. The occurrence of only short-styled morphs 
in the Amazonian variety results from the fact that the plants are 
propagated vegetatively by cuttings, in contrast to Andean coca 
which is grown mainly from seeds. In Amazonia, entire planta- 
tions may be based on a single short-styled clone. 
Since only one stylar form is present in Amazonian coca, 
there is, under field conditions, no fertilization in this obligately 
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