strongly reclinate leaflets. At Sio Felipe, on the upper 
Rio Negro, where several hundred trees were seen, there 
would seem to be a tendency for the leaflets to be hori- 
zontal-reclinate, with some approaching a definitely hori- 
zontal disposition. Whether or not there are definite 
regional tendencies, it is not possible to say, but I should 
be inclined to doubt that large samples of populations 
of this tree in given localities would show any appreciable 
deviation from a mean in this character. In its predom- 
inantly reclinate leaflet position, which frequently devi- 
ates to horizontal or horizontal-reclinate, Hevea micro- 
phylla again suggests H. Benthamiana. 
In 1910, Pax described a variety of Ule’s Hevea mi- 
crophylla—var. major—on the basis of variation in leaf 
size. In 1947, after an examination of the several Ule 
collections at Kew, I wrote: (Schultes, loc. cit. 4) 
‘*There are no valid reasons whatsoever for Pax’s crea- 
tion of Hevea microphylla var. major. Pax gives as his 
basis for the variety ‘foliola majora, angustiora,’ but Ule 
6023 and 6026 as well as Duche 7027 and Ducke HJ BR 
23750 show all possible intergradation in the size of the 
leaflets, and this is known to be a character of little tax- 
onomice value in Hevea.”’ After having seen hundreds 
of trees in the forests and making herbarium collections 
of representative individuals, I can state that Hevea mi- 
crophylla is unusually variable in regard to the size and 
even the shape of the leaflets. The very great majority 
of the trees live up to the specific epithet, having rela- 
tively small leaflets which are elliptic or, more usually, 
lanceolate-elliptic, apically very long-acuminate, and 
measuring 7-10 cm. long and 2.5-8.5 cm. wide. Some 
trees (as may be seen in Schultes & Lopez 9691, however, 
have very broadly elliptic-ovate leaflets with very short 
or even abruptly acuminate tips and measuring up to 
9.5-12 cm. long and 4.7 cm. wide. These are extreme 
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