to produce fruit. Most of the nine ‘Amar6n’ fruits col- 
lected fall within the ‘Buyés’ variation pattern; two are 
the same as ‘Quinde’. A single ‘Buyés’ tree (Bristol 
1109, 1193) has unusually long (11.7-24.7 em.), more 
narrow fruits which are not included in Plate LI. Meas- 
urements were made on ripe fleshy fruits. 
Leaf variation 
Despite the highly conspicuous and attractive flowers 
of all the cultivars, the leaves are the centre of interest 
to the natives, to whom they are the structures of prin- 
cipal economic importance. Plate LII depicts a repre- 
sentative leaf of each cultivar. The striking malforma- 
tion in four of the cultivars has led to statements that 
the plants are diseased, probably by viruses, or that they 
are ‘‘ ‘virus-races’ *” (8, 22, 85, 36). 
Recently, Robert Kahn and R. Bartels have isolated 
a previously unknown virus from several of the cultivars, 
including ‘Buyés’ which never has erose or otherwise 
malformed leaves (21). These investigators have named 
the virus Colombia Datura Virus (CDV) and report that 
its symptoms in Datura are leaf distortion, mottling or 
yellowing, but that sometimes there are no symptoms. 
Leaves of the common D. candida ‘Buyés’ in the Valley 
of Sibundoy are never distorted, and mottling and yel- 
lowing, if present, are rare. 
It seems probable that there is no direct causative re- 
lationship between CDV and leaf shape in the D. can- 
dida cultivars. At the same time, the genetic control of 
leaf shape is enigmatic, for careful examination of the 
irregularly leaved cultivars will disclose on every plant 
a few small to medium sized ovate and entire leaves, as 
in “Buyés’. These leaves invariably occur on one or two 
branches which are growing more rapidly than all others 
on the plant. Given this exception, it is tempting to pos- 
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