(1910) 124) repeated this, stating: ‘‘calyx.... utriusque 
sexus intus tomentellus.’’ I find it difficult to reconcile 
this with my own observations on flowers from both the 
type and from the new material, but I think we may be 
justified in assuming that there is some variability in this 
character and that the normal condition is a glabrous 
interior of the pistillate calyx. 
Hemsley (loc. cit. fig. 13) has also published a sketch 
of the ovary showing a sericeous indumentum covering 
all parts of the ovary. Mueller- Argoviensis (loc. cit.) and 
Pax (loc. cit.) both indicate ‘‘ovarium glabrum”’; this 
coincides with my own observations. 
Relationships of Hevea rigidifolia 
There has been some difference of opinion with regard 
to the closest affinities of Hevea rigidifolia. Mueller- 
Argoviensis, in his description of Hevea nitida, wrote: 
‘‘evidenter affinis H. rigidifoliae et H. brasilensis.’? In 
a detailed consideration of generic subdivisions in Hevea, 
Huber (in Bol. Mus. Paraense 4 (1906) 622, 632) in- 
cluded Hevea rigidifola in the section Bisiphonia, series 
Luteae, together with HZ. lutea (Benth.) Muell.-Arg.,” 
H. cuneata Hub.," H. Duckei Hub.,” HH. paludosa 
Ule, HW. apiculata Baillon”® and H. Benthamiana Muell.- 
Arg. 
Huber’s statements regarding the relationships of 
Hevea rigidifolia should be of interest because of his 
vast knowledge of the genus, although it is probably 
true that, due to his confusion of an unusual variant of 
H. Benthamiana from the Rio Negro with H. rigidifolia, 
Now considered to represent Hevea guianensis var. lutea. 
14 poorly understood concept representing possibly a form of Hevea 
guianensis. 
” Now included by Ducke as a synonym of Hevea Benthamiana. 
® Probably a variant of Hevea guianensis. 
[ 115 ] 
