which are borne on the branchlets, are very minute and 
‘annot be seen from the ground, even with binoculars. 
Dr. Adolpho Ducke, who has visited the upper Rio 
Negro basin several times, was unable to collect flowering 
material of weuqui, although he devoted special attention 
to this tree which he believed represented an undescribed 
species. Without flowering material, however, there was 
some question as to even its generic affinities. 
When we began our work in the upper Rio Negro in 
late 1947, Dr. Ducke counseled us to try to find flower- 
ing material which would settle definitively the identity 
of ueugui. With this in mind, we studied a number of 
individuals over a wide area. It was almost always neces- 
sary to use the balatero’s climbing-irons (employed dur- 
ing the extraction of balata from species of Manilhara), 
since the girth of the tree usually prevented the use of 
the ‘‘peconha”’ (a band of pounded bark which the In- 
dians place on the feet to aid them in climbing). The 
expertness of our assistant, the late Francisco L6pez, in 
the use of the climbing-irons greatly increased the num- 
ber of trees which we could study. 
During October and November, this work was carried 
on principally by Murea Pires. At first, sterile specimens 
only were obtainable. Then, gradually, we began to se- 
cure material which was in bud. No flowers, however, 
were found, and we later learned that the species develops 
the flower with extreme slowness, persisting in bud some- 
times for three or four months. Many experiments were 
tried to force the buds to open: sun, artificial heat, soak- 
ing in hot and warm water; but all these efforts failed. 
It is interesting in this connexion to note how little 
the natives know about the life-history of this species, 
even though it is one of their common and useful plants. 
Repeated questioning on our part brought forth the most 
divergent and amusing remarks concerning the flowering 
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