texture, it would be obvious that the Madeira collection 
is specifically distinct from Cunuria Spruceana. 
One could easily suspect that the Rio Madeira material 
represents a combination of characters from two species, 
in which case there might be apprehension that a specific 
name is being assigned to a segregant from interspecific 
crossing. Cunuria crassipes, apparently an extremely 
localized endemic of the Rio Negro area, could be con- 
sidered one parent of such an hypothetical hybrid, and 
C. Spruceana, also known only from a region far to the 
north of the Rio Madeira, the other. Possibly future ex- 
ploration may turn up material of Cunuria Spruceana 
and C. crassipes in the Rio Madeira. These species grow 
in caatingas, often in association with Hevea rigidifolia, 
Hf, viridis and H. pauciflora var. coriacea (possibly cor- 
rectly called H. confusa). All these plants, when ‘‘pure,”’ 
seem to have precise ecological requirements, and these 
requirements are similar for each of the species cited. It 
is interesting, therefore, that Hevea viridis is known from 
Borba on the Rio Madeira and that HY. camporum (which 
Ducke is considering as possibly a form of H. pauciflora 
var. corvacea and which Baldwin would refer to HZ. con- 
JSusa) is known from the great plateau at the headwaters 
of the Rio Marmellos, an affluent of the Madeira. These 
localities are not distant from the general region where 
the type material of Cunuria australis was found. It 
would not be surprising, therefore, to discover in this 
area additional species of Cunuria or any of the already 
recognized species. Certainly the requisite ecological con- 
ditions exist in the Madeira Valley. 
2. Cunuria crassipes Mueller Argoviensis in Mar- 
tius FJ. Bras. 11, pt. 2 (1874) 510; Corréa Diccion. PI. 
Uteis Brasil. 2 (1981) 482; Pax in Engler Pflanzenr. IV. 
147 (Heft 42) (1918) 17. 
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