Téen. Inst. Agron. Norte no. 10 (1946) 19) himself pub- 
lished this opinion. Baldwin likewise had arrived at a 
similar conclusion, stating (in Journ. Hered. 38 (1947) 
59): ‘‘And it is my opinion that FZ. camporum ... will 
be found to have the same relation to HZ. confusa that 
var. tovicodendroides does to H. viridis, they perhaps 
being ecotypes and nothing more. 
Another concept which I am referring to Hevea pauci- 
flora var. coriacea is H. humilior, described by Ducke in 
1929 on the basis of small trees found growing on the 
outskirts of Iquitos, Peru. Since that time, Ducke, 
Baldwin, and Seibert have visited the region and have 
studied individuals of this concept. I have made four 
visits to what I believe to be the same colony of trees 
from which the type came (in a swampy pasture near the 
cemetery on the Morona-Cocha road) and have given 
much thought to the possible relationship of Hevea hu- 
milior to very similar individuals of HZ. pauciflora var. 
coriacea which I have seen near Leticia on the Rio Ama- 
zonas and in the upper Rio Negro basin. I have come 
to the conclusion that Hevea pauciflora var. coriacea and 
Hi. humilior belong to the same concept. 
Ducke (in Bol. Téen. Inst. Agron. Norte no. 10 (1946) 
17) was the first to point this out, after he had revisited 
the type locality in 1945, and had restudied the problem 
in the light of knowledge he had gained in his experience 
with Hevea pauciflora var. coriacea in the Rio Negro. 
He wrote: [translated] ‘* Trees of very low stature which 
were found on the outskirts of that city furnished me 
nineteen years ago with botanical material which served 
to create the supposed species humilior which | am now 
obliged to extinguish because it does not present a single 
character to separate it from pauciflora var. coriacea of 
the Solimoes and Rio Negro.” 
In 1947, Baldwin stated: ‘‘In the marshes around 
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