only on the edge of the drier land, not out in the per- 
manent igap6 vegetation (chiefly Ambelania sp.) of the 
lake itself. Hevea microphylla has a number of invariable 
companions in this region (Sio Felipe), and these actu- 
ally serve as indicators. A Clusia with enormous leaves, 
Leopoldinia pulchra (the yara palm), a beautiful species 
of Ouratea, Henriquiezia verticillata, a medium-sized 
Bombax with a large red flower, sometimes Mauritiella 
aculeata, and, most striking of all, Moronobea pulchra 
are found occupying the same association. A species of 
Manilhkara—exploited for chicle—also accompanies these 
plants.” 
Opposite Uanadona on the Rio Negro, slightly below 
the mouth of the Rio Dimiti, the interesting Igarapé 
Badaiti meanders into the hinterland through dense 
swamp and lake areas. My notes concerning this area 
state: ‘‘Along the banks of the Rio Negro in this re- 
gion, Hevea Benthamiana is common. Going up the 
igarapé (creek), one finds several caatingas: we visited 
two—one caatinga-forest and one low, sandy, open 
caatinga. In the former, we found Cunuria crassipes ex- 
cessively abundant—Just finishing flowering and some 
with large, reddening fruits. ... Continuing up the 
igarapé, one sees a little Hevea Benthamiana wherever 
there is slightly flooded ground. Farther up, Hevea mi- 
crophylla, untortunately now all over flowering and fruit- 
ing, begins to appear. At first it is tall—as at Sao Felipe 
—up to 55 feet in height, but with the typical sparse 
crown. Where inundation is still deeper—up farther in 
the igarapé—the tree becomes a much smaller individ- 
ual, very like those at Nibarti, the type locality.” 
The botanically unknown Rio Dimiti is unusually in- 
teresting, principally because it rises in the fascinating 
and mysterious mountains of the Cauaburi. Excerpts 
from my notes (May 14, 1948) of a rapid trip along this 
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