ation worthy of note, the very large leaves having a 
petiole of about the same size as the smaller, mature 
leaves. 
Sufficient flowering material is not yet available for 
an appraisal of the variation in floral characters. The 
constancy in characters of the fruiting structures would 
tend to suggest little, if any, in the floral structures. 
AFFINITIES OF HEVEA MICROPHYLLA 
It would, perhaps, be premature to suggest with any 
definiteness the closest affinities of Hevea microphylla. 
There can be no doubt, however, but that this is the 
most outstandingly distinct species of the genus and is 
really closely allied to no other species. 
In the unusually large flowers and in the apical twist- 
ing of the calyx lobes, Hevea microphylla somewhat re- 
sembles H. rigidifolia. In the lacerations of the pistillate 
disk, it bears some resemblance to Hevea pauciflora and 
to H. nitida. In the number and placement of the an- 
thers, Hevea microphylla is similar to H. brasiliensis. 
The brilliant red, papery bark on the new flushes of 
Hevea microphylla finds a parallel in H. nitida; whereas 
the bark of the basal portions of the trunk, in color and 
in the ease with which it peels from the cambium, are 
suggestive of H. Spruceana. 
In having leafy shoots or flushes which alternate with 
narrow rings of bud-scale scars (interflush rings), AZevea 
microphylla is grouped, in Seibert’s key (Seibert, loc. cit. 
291-292) with Hevea Benthamiana and H. brasiliensis. 
I am inclined to view this recently discovered character 
which Seibert has called ‘‘interflush short-shoots’’ as 
having possibly a deep significance in an evolutionary 
study of the group, but certainly the other characters 
which Hevea microphylla has in common with HZ. Ben- 
thamiana and H. brasiliensis are few and often superficial. 
[ 129 ] 
